I reloaded my game to investigate my tracker issue and ran into a few obvious bugs (and have more info about the tracker and an associated question)
Bugs:
1. I've seen other map artifact displacements. In particular map additions (resources such as horses, and indigenous people statues) floating above their hexes (the horses at first looked like they were taking a swim in a coastal square). I've also seen (vulcano?) smoke displaced into a salt flat/desert area. Not sure if it was 'floating' too, but it was assurdely not in the right spot. FYI, turn change fixed the problem, but switching viewports prior to turn change did not.
*My appologizes if this is a known issue, I saw the bit on the highlight circle and the unit flag displacements*
2. Similar to the known USA flags issue, the French flags are now appearing as plain yellow. I think when I first encountered them they were normal, but now are plain yellow.
*My appologizes if this is a known issue, I saw the bit on the highlight circle and the unit flag displacements*
Possible Bug/Possible Newbie Misunderstanding:
1. Is it possible to permanently loose national units? If so how, or better yet is it documented somewhere? After further experimentation, it is clearly a case of permanently loosing the ability to build out the missing tracker. The 'Hide Untrainable Units' option is not selected, so its not that. I then self destroyed my remaining 4 trackers, then went to the next turn and entered my city screen. It stated that only 4 Trackers were available to be built. Hunters weren't available to me (currently researching Atlatl) at the time so I don't think its not a case of issue #2 below (unless there is some earlier tech that turns Trackers off?)
2. You are allowed 2 Thieves and 2 Rogues. Rogues replace Thieves. I built my Bandit's Hideout late, after Rogues were available to me. Once it was built the Theif unit disappeared from my city selection options as the Rogue unit became available (i.e. from darkened to lit). Again as noted above the 'Hide Untrainable Units' option was not selected. My initial guess is that once the newer/upgradable unit is available you loose access to the older one. However this isn't exactly a global case, (i.e. that assumption is not true with existing older units). Another experiment led me to learn that I could build 5 Hunters even when I had 4 Trackers still wandering around.