A note before I go any further: I bought RTW off of steam.
Here's how it started: I decided to try Roma Surrectum II, but I couldn't get it to work. After realizing that it didn't mod folder, I deleted all of that and put in my backup copy of RTW. For some reason, it was missing a file, so I reinstalled RTW.
But ever since then, I get the can't find steam error every time I load up ANY mod. Any ideas?
I'm going to try reinstalling on of the mods to see if that works.
EDIT: Reinstalling the mod didn't even work...