Make sure in your SexLab core settings that "Allow Creature Sex" is turned on. I had a similar problem, only to find that the creature allowance setting was turned off. Frustrating, because I always forget to turn it back on in clean saves.
Speaking of which, I'm having an odd anomaly of my own. I'm running a brand new game with Beastess installed, and it seems that every other load or so, the mod will disable itself. I don't touch anything between games, but it seems like quitting and restarting seems to disable the mod and I lose the spells and etcetera... Until reloading the game again, at which point it usually fixes itself.
I imagine this is a conflict with something, but I don't have either of the conflict mods you mentioned.
Does anyone perhaps have a possible explanation for this anomaly?
Other than this, of course, the mod works great, and I'm thrilled to be re-living the beasty exploits of my old Oblivion character~
Edit: Some additional information: Beastess does not even display in Wrye Bash, and the mod only seems to activate if I run from ModOrganizer. This is frustrating and counter-intuitive because I prefer Wrye for all my mod work, but I can't seem to get the two to commingle. Please tell me I don't have to bring ModOrganizer into my life for extended periods
