It is crashing because you are using an outdated forge. the Mindcrack pack is using .473 you need at least .474 like direwolf's pack is using.
http://files.minecraftforge.net/ from the sites download files the most recent version is actually .480But the most recent available version of forge is .467...
Whatever, screw it, I just mashed both packs together in the direwolf20 pack in the launcher. It all works fine other than traincraft and advancedsolars, which conflict with forestry and compactsolars(not exactly a big deal on the latter, both would be silly).
Secondedcan one of the modpack dev's comment on this. slowpoke definitely said mystcraft would be included during the live stream. it was the reason we went with the mindcrack pack and didnt wait for dw20's pack. it would be nice to get some official word on the matter.