It’d be much easier for us to figure this out if you could share the .xrns you’ve created. Please upload it somewhere, or email it to support at renoise dot com
Oh man, good thing I posted in the beginner’s section: the reason it didn’t work was that I manually entered the absolute path in the open file dialoges filename-field (“/tmp/tst.xrns”), instead of changing clicking my way to the right directory. As there was no error from renoise, and it said the file got loaded, I thought it did. But when I instead clicked my way to /tmp and double clicked tst.xrns, it loaded properly.