I think this is not a easy thing to be resolved without access to your sistem, so we need to start from the begining and have patience 
at first sight, looks like some transport is missing in QAS, can you disable the ehancements for your user in QAS and check again? Deactivate an enhancement set in the WebUI for testing purposes
I also would check the transport request and try to find out if is there another team working on the same area of impact (Web UI component, BADI, etc.).
Cheers!
Luis