@Tom Cruise Aye, keep in mind that every Power roll usually only produces one phenomena in the original rules. Multiple Despairs symbols should only give more dice or a bonus to the phenomena roll.
I'd suggest having Lores their own part as skills just as in DH. Because they were special. IE: All the Common, Forbidden, and Scholatic Lores as indidivual skills.
I always liked that. Knowledge is greedily hoarded and distributed in 40k.
Right now I'm working on a Phenomena table using what's given in the DH 2nd ED CRB. Will post it here once I'm ready.