Ok, after getting too frustrated on trying to find the 'offending' mod, I uninstalled, re-installed, added mods, but, no SKSE. I then reloaded from a previous save at level 9. I hadn't started the companion quests yet and wasn't yet bitten by a vampire, and, saw the greybeards to advance main questline. After that, I started Dawnguard and got the VL power to properly work.
I honestly think , it has something to do with the companions' 'gift' to be a werewolf and or catching the vamp disease.