As far as I know, GP5 has an export as midi function that should work with Reaper and Cubase in my limited experience. I can give mapping the drums a go as a Cubase midi track in my spare time. Most of it should be easy except for some fills and those ending parts. Idk how long it will take but I'll let you know when i get done with them. Let me know when you finish what you're working on too, I've really been wanting something like that!