If you’re a Mac user all you need is http://www.apple.com/downloads/macosx/audio/junxion.html. That software will convert any USB device to MIDI. Which means your Rockband drum kit wit appear as a midi controller in just ANY audio software (ProTools, Logic, Garageband, Reason, Cubase, and of course in any plugin supported by these software… Battery 3 from Native instruments, Ezdrummer from ToonTrack, any Apple Loop plugin etc…)

If you’re a PC user, I’m sure you’ll be able to find something that works like Junxion. But I have to admit, Gamepad Companion and other softwares converting usb to keys instead of MIDI signals, will involve a lot of latency.

Forcing your computer to believe you have plugged a MIDI controller is the best way to control any USB device for musical composing!