I cannot get the DEL key to work in the new version--I use it all the time to delete files and folders. Same for CTRL+C and CTRL+V also CTRL+A etc. Seems like the system has been changed. Looked at key code assignments--no luck. As an advanced user it seems like there is too much information -- not sure why basic functions that worked before do not work.
Settings > Customize Toolbars > Toolbars
Select the Menu toolbar. Make sure it is either turned on, or that Always enable this toolbar's keys in Listers is checked for it, near the bottom-right.