As far as I can tell the @keydown stuff does not work in user-commands. Calling the user-command from the lister double-click, or from a toolbar button, always runs it as if shift was not held down.
If I put the same command directly into a toolbar button then it works fine, although I had to add IGNOREQUAL to the second Go command to stop the Shift key from causing it to open a new lister. I also changed the first command to use Go UP BACK which I think is better than Go UP
[quote]@keydown:none
Go UP BACK
@keydown:shift
Go BACK IGNOREQUAL[/quote]