I'd have to actually try this -- possibly there is some incompatibility in the software between the bilinear warp and the 3dQwarp. For me, it would be simplest if you can provide some sample data (e.g., on Dropbox or Google Drive) with copies of the commands you ran. Then I can duplicate what you did, and figure out if (a) there's a mistake in your commands, or (b) there's a mistake in my software, or (c) BOTH.
