I have the same problem, and posted a topic about it a few days ago. I believe these modules are not currently compatible and it will take some coding to fix.
Someone came up with a hack to make CleanURL work with the Collecting module, so there’s some hope this can be made to work. It’s on my to-do list to try and figure this out, I’ll post here if I make any progress.
I wonder if @Daniel_KM is still active here and might have any pointers?