Unfortunately, not all of WinVN's functions can be done via the keyboard. Also, some WinVN windows don't support all the normal Windows key functions. This is because they are custom Windows instead of standard Windows. This means that code to do these functions must be included in WinVN.
This is something that is on the 'to do' list (care to get the code and do it?). Each new release of WinVN tends to improve the keyboard function, but somethings get put on the "back burner" in favor of other features or actually requires some major rewriting. It doesn't hurt to ask for a keyboard function to be added. However, before asking, try the latest version, it may have already been added.
[from Greg Monroe]