If you are talking about units, before you start you need to install the ia/iu base, mine or someone else's, and follow the instructions on how to enable and configure it

hi,
super confused as its not showing up in game.
can only select the versions i like, or must i install all and disable the ones I don't want?

The collection is constantly being updated, there are also architectural mods, but not all of them are publicly available because there is no time to test and fix possible errors

whoa