Invalid data files?

In order to keep the space used by SE5 on my hard drive low I tend to compress the pitctures, sounds and empires in .rar until I want to play the game.

This time around I also compressed my gametypes. However when I uncompressed everything and opened a saved game it said I had an invalid data file and I should check to see if my data files are the same as the hosts.

Weird thing was I can press the 'ok' button and play normally as if there was no problem with my gametypes. This occurs on normal SE5 and mods.