OK here goes... You have listed Forge 1.2.2 as a required version for IC2. Thing is, Forge 1.2.2 is bug ridden and causes issues with RP2.
Is Forge 1.2.2 really needed or can we get away with Forge 1.2.0? If we can't then BAAAAAAAAAAAAAW!
Because then we have to wait for.... Yeah you get my point
I shall test 1.42 soon (ish) and see if it works with Forge 1.2.0 but in the mean time i am just checking with others AND letting them know that RP2 might have problems with Forge 1.2.2... Bug problem for all those Nuclear Engineers waiting for those OP retrievers.