Deleting files from the thumbnail panel changed between v4.00 and v4.01. All through the beta and up to release v4.00, I was always able to delete files permanently (bypassing the recycle bin) from the thumbnail panel by first selecting the files and holding the {Shift}+{DEL} keys. This is the standard key combination for permanently deleting files using Windows Explorer. Using this key combination, the pop-up would confirm that I wanted to permanently delete the files. Just selecting the {DEL} key would confirm delete and send to the recycle bin.
Starting in v4.01, holding the {Shift}+{DEL} doesn't provide the option to delete files permanently. There seems to be no way to bypass the recycle bin as in prior versions. Can you restore this functionality if it wasn't intentionally removed?