I'm part way through editing the girlsx files from all the WM EX packs I downloaded - removing all the additional traits that thefuture added (lv1 exhibitionist, average boobs, basic magic, etc), and replacing Bestiality with OralSex - it doesn't take that long (or wouldn't if I hadn't downloaded practically every single WM EX GPAC anyway!) and I think they should work ok - are those tweaks enough to get a WM EX GPAC working with this patch or is there something else I should edit?
Not really... you also need to modify the girls' stats to balance them with the other girls. Random girls should have their minimums and maximums set to have an average of 20 in their stats, and their maximums should average 40, except beauty which should average 60 and have a maximum of 80. Their skill minimums and maximums should give them an average of 10 in their skills, with an average maximum of 30. This is all before positive and negative traits are considered.
Make sure you remove any trait not listed in the coretraits.traits file for my version. They will cause errors in the game. Also, spelling and capitalization counts. Make sure you use the same case and spelling as what is in the coretraits file.
Once a girlsx or rgirlsx file has been edited to be 'valid' for my version, it can be loaded in the girls editor that comes with my version. It can be found in Docs&Tools\Character & Item Editor, named WMEdit (Thank GonDra for making the girls editor compatible with this). It also might just be easier to delete the existing girls and random girls files, and create them from scratch in the girls editor.