Is is really not possible, and I don’t think it will be. If you want these features, simply move the files to Chest. Honestly, this “Move” action is rather useless and causing mostly troubles (as you described) - it might be the best thing simply to remove this feature from avast!.
That’s probably because Explorer is “touching” these files, so that the on-access protection detects access to the infected files. It is certainly not a good idea to stop the scanning of the on-access protection; if you really want that, you can turn the provider off from the avast! On-Access Scanner control panel, or put the folder to the list of avast! exlusions (in the Standard Shield settings), as Eddy suggested.