WOW, I just found that the QtGui-WP34s can display an extra window with the stack registers (in the menu 'Debug') - really a nice feature! :-)
An additional window for the registers 00-99 would also be a great enhancement (maybe 10 regs at a time with a +/- or up/down button).
And of course these separate stack/reg windows would also be great in the usual wp34sgui.exe - Marcus? ;-)