It takes me about 7-10 minutes to load the first time (+3min for map) and 2-4 minutes to load subsequent times without restarting (with a map loading that's quite quick)
A long while ago, I tried v25. Or at least I tried to. It would open up all right, but when it came to loading the map and engine it froze, and then suddenly quit process. Nowhere to be seen in task manager.
A few days ago, I remembered that I still had this mod taking up +2GB of space. I decided to download the current v31 and hey presto! It works now, and I currently have spent over 5 hours on 200 turns, but I'm still well in the Prehistoric Era (Gigantic, 25 Civs, Archipelago, Snail Pace). Wow this is going to take a while, and it takes a while processing AIs' turns as well. Maybe I shouldn't have chosen these settings. But it's a brilliant experience so far, it's just that thinking of all these units and techs... 500 hours?
Also with autoloading the mod, I modified the C2C shortcut in the mod folder to the right target directories and also changed the icon to the C2C one. Default is an ugly blank.