2. tag/untag
I just noticed that the space key has the tag/untag function. Ctrl+R untags all files. What should happen if some of the selected files are tagged and some are not? By now with the space key the tagging is inverted. The menu point "Tag current (T)" tags all selected files (while T does not work yet).
After you tag some files, the rename (and copy, and move, and maybe etc.) operation works for the tagged files, not for the selected files.
As far as I tested the tag function:
The behaviour is the same as if I select files whith right click in my file manager WinNC.net. The tagging fixes the selection. As soon as at least one file is tagged all actions refer to the tagged file(s). The selection by mouse (blue background) has only effect for tagging.
From this state of information there is no need/possibility to search by tag.
Any good idea? The feature has to be explained in the help and WhatsNew.