I have quite a few cities, 12 civs and 24 CSs.
It is 1710 AD and if I open IGE:
[253079.048] Initializing Lua 5.1.4
[253156.450] InstalledPanel: Refreshing Mods
[253156.450] InstalledPanel: GetModBrowserListings()
[253156.453] InstalledPanel: Refreshing Mods
[253156.453] InstalledPanel: GetModBrowserListings()
[253156.457] InstalledPanel: Refreshing Mods
[253156.457] InstalledPanel: GetModBrowserListings()
[253158.590] InstalledPanel: Refreshing Mods
[253158.590] InstalledPanel: GetModBrowserListings()
[253168.447] InstalledPanel: Refreshing Mods
[253168.447] InstalledPanel: GetModBrowserListings()
[253168.450] InstalledPanel: Refreshing Mods
[253168.450] InstalledPanel: GetModBrowserListings()
[253212.902] CivilopediaScreen: SetSelectedCategory(12)
[253212.920] CivilopediaScreen: CivilopediaCategory[CategoryTerrain].DisplayList
[253212.928] CivilopediaScreen: SetSelectedCategory(1)
[253212.928] CivilopediaScreen: CivilopediaCategory[CategoryHomePage].DisplayList
[253213.623] Tutorial: Loaded Additional Tutorial checks - Assets\DLC\Expansion\Tutorial\lua\TutorialInclude_Expansion1.lua
[253214.333] GenericPopup: Loaded Popup - Assets\DLC\Expansion\UI\InGame\PopupsGeneric\DeclareWarMovePopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\DLC\Expansion\UI\InGame\PopupsGeneric\PuppetCityPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ConfirmImprovementRebuildPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\NetworkKickedPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\CityPlotManagementPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ConfirmCommandPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\MinorCivEnterTerritoryPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\LiberateMinorPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ReturnCivilianPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\AnnexCityPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\DeclareWarMovePopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\BarbarianRansomPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ConfirmGiftPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ConfirmCityTaskPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\PuppetCityPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\DeclareWarRangeStrikePopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ConfirmPolicyBranchPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\MinorCivGoldPopup.lua
[253215.303] ChoosePantheonPopup: -252
[253215.303] ChoosePantheonPopup: 963
[253215.304] ChoosePantheonPopup: 711
[253215.427] EspionageOverview: Refreshing Agents
[253215.431] EspionageOverview: Refreshing My Cities
[253215.455] EspionageOverview: Refreshing their Cities
[253215.740] IGE_Controller_All: ****************************************************************
[253215.740] IGE_Controller_All: Starting...
[253215.816] IGE_Overlay: loaded
[253215.821] IGE_CityBanner: loaded
[253215.848] IGE_MiniMap: loaded
[253215.864] IGE_TabsBar: IGE_TabsBar
[253215.874] IGE_ActivePlayerSelection: IGE_ActivePlayerSelection
[253215.917] IGE_RiversElement: IGE_RiversElement
[253215.927] IGE_TerrainPanel: IGE_TerrainPanel
[253215.942] IGE_CitiesPanel: IGE_CitiesPanel
[253215.955] IGE_UnitsPanel: IGE_UnitsPanel
[253215.967] IGE_PlayersPanel: IGE_PlayersPanel
[253215.977] IGE_TechsPanel: IGE_TechsPanel
[253215.988] IGE_PoliciesPanel: IGE_PoliciesPanel
[253216.007] IGE_ConfirmPopup: IGE_ConfirmPopup
[253216.044] IGE_Window: IGE_Window
[253216.044] IGE_Window: IGE_ShareGlobalAndOptions
[253216.044] IGE_Window: IGE_SharingGlobalAndOptions, IGE=...
[253216.044] IGE_Window: IGE loaded
[253217.825] Demographics: Dequeuing demographics
[253217.825] Demographics: Dequeuing demographics
[253462.092] IGE_Window: IGE_PingAllVersions, data=...
[253462.114] IGE_Window: IGE_Initialize
[253462.114] IGE_Window: IGE:Gods and kings=true
[253462.114] IGE_Window: IGE_TabsBar.OnInitialize
[253462.119] IGE_Window: IGE_TabsBar.OnInitialize - Done
[253462.123] IGE_Window: IGE_TerrainPanel.OnInitialize
[253462.184] IGE_Window: IGE_RegisterTab, ID="TERRAIN_EDITION", name="Terrain (F1)", icon=0, group="edit"
[253462.184] IGE_Window: IGE_SelectedPanel, ID="TERRAIN_EDITION"
[253462.184] IGE_Window: IGE_RegisterTab, ID="TERRAIN_PAINTING", name="Terrain (F3)", icon=0, group="paint"
[253462.184] IGE_Window: IGE_TerrainPanel.OnInitialize - Done
[253462.237] IGE_Window: IGE_RegisterTab, ID="CITIES_AND_UNITS", name="Cities And units (F2)", icon=1, group="edit"
[253462.237] IGE_Window: IGE_UnitsPanel.OnInitialize
[253462.266] IGE_Window: IGE_RegisterTab, ID="UNITS", name="Units (F4)", icon=2, group="paint"
[253462.266] IGE_Window: IGE_UnitsPanel.OnInitialize - Done
[253462.270] IGE_Window: IGE_RegisterTab, ID="PLAYERS", name="Players (F6)", icon=3, group="change"
[253462.320] IGE_Window: IGE_TechsPanel.InitializeHelp
[253462.489] IGE_Window: IGE_RegisterTab, ID="TECHS", name="Technologies (F7)", icon=4, group="change"
[253462.489] IGE_Window: IGE_PoliciesPanel.OnInitialize
[253462.504] IGE_Window: IGE_RegisterTab, ID="POLICIES", name="Social Policies (F8)", icon=5, group="change"
[253462.504] IGE_Window: IGE_PoliciesPanel.OnInitialize - Done
[253462.505] IGE_Window: Initialization completed
[253462.505] IGE_Window: IGE_Showing
[253462.527] IGE_Window: Updating fog
[253462.527] IGE_Window: SetFog - begin
[253462.527] IGE_Window: Updating fog - done
[253462.648] IGE_Window: OpenCore - step1
[253462.648] IGE_Window: OpenCore - step2
[253462.648] IGE_Window: OpenCore - done
[253462.648] IGE_Window: SaveFile - begin
[253462.648] IGE_Window: Get files list
[253462.770] IGE_Window: Get first free index
[253462.787] IGE_Window: Get oldest index
[253462.802] IGE_Window: Deleting
[253462.805] IGE_Window: Deleting IGE1
[253462.805] IGE_Window: \Users\akivajohnson\Library\Containers\com.aspyr.civ5campaign\Data\Library\Application Support\Civilization V Campaign Edition\Saves\single\IGE1.Civ5Save
It is 1710 AD and if I open IGE:
[253079.048] Initializing Lua 5.1.4
[253156.450] InstalledPanel: Refreshing Mods
[253156.450] InstalledPanel: GetModBrowserListings()
[253156.453] InstalledPanel: Refreshing Mods
[253156.453] InstalledPanel: GetModBrowserListings()
[253156.457] InstalledPanel: Refreshing Mods
[253156.457] InstalledPanel: GetModBrowserListings()
[253158.590] InstalledPanel: Refreshing Mods
[253158.590] InstalledPanel: GetModBrowserListings()
[253168.447] InstalledPanel: Refreshing Mods
[253168.447] InstalledPanel: GetModBrowserListings()
[253168.450] InstalledPanel: Refreshing Mods
[253168.450] InstalledPanel: GetModBrowserListings()
[253212.902] CivilopediaScreen: SetSelectedCategory(12)
[253212.920] CivilopediaScreen: CivilopediaCategory[CategoryTerrain].DisplayList
[253212.928] CivilopediaScreen: SetSelectedCategory(1)
[253212.928] CivilopediaScreen: CivilopediaCategory[CategoryHomePage].DisplayList
[253213.623] Tutorial: Loaded Additional Tutorial checks - Assets\DLC\Expansion\Tutorial\lua\TutorialInclude_Expansion1.lua
[253214.333] GenericPopup: Loaded Popup - Assets\DLC\Expansion\UI\InGame\PopupsGeneric\DeclareWarMovePopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\DLC\Expansion\UI\InGame\PopupsGeneric\PuppetCityPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ConfirmImprovementRebuildPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\NetworkKickedPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\CityPlotManagementPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ConfirmCommandPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\MinorCivEnterTerritoryPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\LiberateMinorPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ReturnCivilianPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\AnnexCityPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\DeclareWarMovePopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\BarbarianRansomPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ConfirmGiftPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ConfirmCityTaskPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\PuppetCityPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\DeclareWarRangeStrikePopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\ConfirmPolicyBranchPopup.lua
[253214.333] GenericPopup: Loaded Popup - Assets\UI\InGame\PopupsGeneric\MinorCivGoldPopup.lua
[253215.303] ChoosePantheonPopup: -252
[253215.303] ChoosePantheonPopup: 963
[253215.304] ChoosePantheonPopup: 711
[253215.427] EspionageOverview: Refreshing Agents
[253215.431] EspionageOverview: Refreshing My Cities
[253215.455] EspionageOverview: Refreshing their Cities
[253215.740] IGE_Controller_All: ****************************************************************
[253215.740] IGE_Controller_All: Starting...
[253215.816] IGE_Overlay: loaded
[253215.821] IGE_CityBanner: loaded
[253215.848] IGE_MiniMap: loaded
[253215.864] IGE_TabsBar: IGE_TabsBar
[253215.874] IGE_ActivePlayerSelection: IGE_ActivePlayerSelection
[253215.917] IGE_RiversElement: IGE_RiversElement
[253215.927] IGE_TerrainPanel: IGE_TerrainPanel
[253215.942] IGE_CitiesPanel: IGE_CitiesPanel
[253215.955] IGE_UnitsPanel: IGE_UnitsPanel
[253215.967] IGE_PlayersPanel: IGE_PlayersPanel
[253215.977] IGE_TechsPanel: IGE_TechsPanel
[253215.988] IGE_PoliciesPanel: IGE_PoliciesPanel
[253216.007] IGE_ConfirmPopup: IGE_ConfirmPopup
[253216.044] IGE_Window: IGE_Window
[253216.044] IGE_Window: IGE_ShareGlobalAndOptions
[253216.044] IGE_Window: IGE_SharingGlobalAndOptions, IGE=...
[253216.044] IGE_Window: IGE loaded
[253217.825] Demographics: Dequeuing demographics
[253217.825] Demographics: Dequeuing demographics
[253462.092] IGE_Window: IGE_PingAllVersions, data=...
[253462.114] IGE_Window: IGE_Initialize
[253462.114] IGE_Window: IGE:Gods and kings=true
[253462.114] IGE_Window: IGE_TabsBar.OnInitialize
[253462.119] IGE_Window: IGE_TabsBar.OnInitialize - Done
[253462.123] IGE_Window: IGE_TerrainPanel.OnInitialize
[253462.184] IGE_Window: IGE_RegisterTab, ID="TERRAIN_EDITION", name="Terrain (F1)", icon=0, group="edit"
[253462.184] IGE_Window: IGE_SelectedPanel, ID="TERRAIN_EDITION"
[253462.184] IGE_Window: IGE_RegisterTab, ID="TERRAIN_PAINTING", name="Terrain (F3)", icon=0, group="paint"
[253462.184] IGE_Window: IGE_TerrainPanel.OnInitialize - Done
[253462.237] IGE_Window: IGE_RegisterTab, ID="CITIES_AND_UNITS", name="Cities And units (F2)", icon=1, group="edit"
[253462.237] IGE_Window: IGE_UnitsPanel.OnInitialize
[253462.266] IGE_Window: IGE_RegisterTab, ID="UNITS", name="Units (F4)", icon=2, group="paint"
[253462.266] IGE_Window: IGE_UnitsPanel.OnInitialize - Done
[253462.270] IGE_Window: IGE_RegisterTab, ID="PLAYERS", name="Players (F6)", icon=3, group="change"
[253462.320] IGE_Window: IGE_TechsPanel.InitializeHelp
[253462.489] IGE_Window: IGE_RegisterTab, ID="TECHS", name="Technologies (F7)", icon=4, group="change"
[253462.489] IGE_Window: IGE_PoliciesPanel.OnInitialize
[253462.504] IGE_Window: IGE_RegisterTab, ID="POLICIES", name="Social Policies (F8)", icon=5, group="change"
[253462.504] IGE_Window: IGE_PoliciesPanel.OnInitialize - Done
[253462.505] IGE_Window: Initialization completed
[253462.505] IGE_Window: IGE_Showing
[253462.527] IGE_Window: Updating fog
[253462.527] IGE_Window: SetFog - begin
[253462.527] IGE_Window: Updating fog - done
[253462.648] IGE_Window: OpenCore - step1
[253462.648] IGE_Window: OpenCore - step2
[253462.648] IGE_Window: OpenCore - done
[253462.648] IGE_Window: SaveFile - begin
[253462.648] IGE_Window: Get files list
[253462.770] IGE_Window: Get first free index
[253462.787] IGE_Window: Get oldest index
[253462.802] IGE_Window: Deleting
[253462.805] IGE_Window: Deleting IGE1
[253462.805] IGE_Window: \Users\akivajohnson\Library\Containers\com.aspyr.civ5campaign\Data\Library\Application Support\Civilization V Campaign Edition\Saves\single\IGE1.Civ5Save