I can safely say these are not problems with any of your EPs or the latest Inteen.
Unable to change to outerwear is probably a problem with a clothing/dresser mod you have. Unable to get 2 sims to marry sounds like it could be mod/hack problem too.
Download and run
Paladin's HCDU and see what mods are conflicting. If you can't make head or tails of the results of HCDU, post it here and someone will help.