In order to answer my own questions.
First, my rant about options not showing up. I am quite new at Sims4 and it turns out the 'More Choices' doesn't work the way I thought it would. When choices are many, each time you hit it, it will show a random selection of the remaining (not currently shown) available choices. Something like that. Meaning that you have to keep hitting 'More Choices' until the one you need shows up.
Second, in order for Cum Consumption to work there have to be animations with the appropriate tag. There is definitely something afoot here because I had hard time making the tags stick to animations. I'd 'modify' the animations, verify that they in fact have the new tag and yet, to no effect. Restart the game, the new tags vanish. I still don't know why this happens, but eventually I managed to make them stick. I don't know if this is it, but I tried 'merging' the modification sets, saved a new json file (from the game, not directly on disk). Weird, contraintuitive procedure. Anyhow, since then the tag sticked and sims are consuming like crazy.
