May sound like a dumb question, but you are submitting the post (by clicking "post reply" or "post new thread") after you upload the files? I have heard before of some people not submitting the post after uploading files, so what ends up happening is you upload the files and they go to the temp folder but are eventually purged because the post is never created so they're never moved to a gallery folder.
Your ImageMagick version shouldn't matter, your system should have something semi current. You'll want to make sure the paths are populated correctly (the
UBB.threads System Requirements Test will tell you where it detects them at).
