Finally, after working out the answer to the question just so I can register, made it onto the forum.
I bought and solved my ISIS puzzle years ago and it's stuck with a few mm gap in the middle at 180 degrees. I've taken apart the puzzle and put it together a few times until I accidentally locked the parts when reassembling. It may be one of the internal parts (don't want to spoil) might have been out of place and caused it to lock. I can see, I think, one of them behind the middle loose band. Should I be prodding this out the way to fix the issue? Or can someone PM me some assistance. It appears any kind of help is hidden behind PM-ing or the 5% club so if someone can message me or add me to 5% board that would be very helpful.
Thank you!!