I would just like to say that if you install the Apoc files properly you should NOT have a problem. The mod uses absolutely nothing that isn’t already used somewhere else in the game (other than the landscape files) so there should be no problem. Plenty of people download and install it with no problems whatsoever (other than the occasional complaint that sound becomes disabled). So basically, as long as all the files wind up where they need to be, it shouldn’t be a problem.
What kind of issues are you having? Perhaps I can help.