We fixed the weirdness with trying to add points while drinking the Draught of Reconfiguration. Now you should be able to add points just fine and your options won’t be greyed out.
Fixed in Patch 1.52.100
Getting rid of Deadened Emotions is the whole REASON I'm trying to get the vampire-reconfiguration to work, so I hope EA fixes the problem TheTenz reports, too. I'm going to try the workaround Punikki89 suggested to see if the talents on the power/weakness window will stop fading out on me so I can actually complete the desired reconfiguration, and it'll be extremely annoying if the Dampened Emotions 'power' persists despite all efforts to remove it.
Note: Dampened Emotions are rather inconvenient for certain occupations. : /
Update: The workaround solved the problem of the fading talent buttons/windows, and I redid my vamp's 'talent tree' so she no longer has any points in Dampened Emotions. For a brief time the Dampened Emotions buff disappeared. I saved and then quit the game, cleared my TS4 caches, emptied the trash folder, & shut down & restarted my computer, as I've learned to do after every TS4 gameplay session. Coming back to play just now, there's my vampire with the DAMPENED EMOTIONS buff dominating all the other buffs. She has ZERO points in Dampened Emotions. That buff should be GONE.
Later, same evening: the Damp'd Emotions buff disappeared after the Vamp walked into the kitchen, seemingly overwhelmed by a number of items that give off an Inspired buff, & it hasn't come back yet. Have traveled to a number of different lots. Haven't rotated out to another household yet; will try to remember to report back after I play another family & return to vamp.
Jan. 5 2019: Rinse & repeat. Started up my game (caches & trash can emptied last night, computer shutdown & restarted), entered vamp's home, & she had 'suppressed emotions' buff tacked on at the end of all her focused buffs. I had her travel to another lot, & the should-be-impossible-to-have buff was gone. I'm noticing that the name of the buff is changing as if the game were recognizing some kinda change in the number of points, just not the correct/final change: 0 points.
I’ve wondered if fame is bugged as well because my sim can’t eat and will frequently earn the quirk of not being able to eat low quality food... sadly, it happens even if the food is of the highest quality. So I can’t have famous sims or vampire sims for risk of them starving to death if I don’t keep up with the cheats.
EVERYONE I HAVE FOUND A WORKAROUND! (PC only I'm afraid)
With MC Command Center you are able to remove buffs/traits. Here's what you need to do: download and install MCCC > testingcheats on > right click your sim > head over to MC Command Center > MC Cheats > Cheat Sim info > Mood/Buff Control > Remove Buff and then remove the vampire weaknesses you don't want one by one.
EDIT: Apparently everytime you restart the game it resets which means you have to do it again everytime you start the game
Unfortunately this is what I have had to do as well. Removing the buffs every time I play with MCCC has been the only way I've been able to play after drinking the reconfiguration potion. I even tried humanizing and re-turning my vamps to see if it might reset, but no such luck.
Some weakness buffs get stuck as well unfortunately, particularly Withered Stomach, Uncontrollable Hissing, and Eternal Sadness. I also find it unfortunate that the withered stomach trait does not allow your vamp to consume plasma fruit salad without getting sick, but not sure if that's a bug or unfortunate gameplay consistency oversight.
