Our little project called re-lab that does clean-room reverse-engineering of file formats recently asked Ardour team is they needed specs for some file formats. Paul replied that REX2 audio loops is one of them. So we started inspected it. Some more information on that is here.
Now here is what we need. All we have right now is a bunch of .rx2 files that I got with my Focusrite Saffire Pro24 and bundled software. It's good for a start, but for proper r-e we need introducing small changes to files and seeing what's changed. So we need someone with a licensed copy of ReCycle and some spare time on his/her hands to help us figuring things out.