Hi Breerents,
Earlier this year I made the mistake of downloading some files via the exchange. First thing I noticed was some of the files installed CC (Custom Content) files into my game. That made me a very unhappy simmer.
Hubby helped me unistall what I had downloaded from the exchange. Told me to look through the Downloads and Installed Contents tabs in the launcher program and delete anything that doesn't quite look right. I went through all the categories - Sims, Lots, Objects and Patterns. As there was some CC in every category. That seemed to help get rid of the files.
I'm not sure if this will entirely help your situation, but I'm hoping it'll help some.
MrsFlynn