When creating a dialog box from a command key shortcut Tcl/Tk Aqua freezes up.
This issue appears in the latest Active Tcl/Tk version for Mac; I think it also happens in the latest 220.127.116.11 build available.
This is related to the bug "https://sourceforge.net/tracker/?func=detail&atid=112997&aid=3285355&group_id=12997" (this bug appears when an error message has to be displayed, with very similar consequences: a freeze and a white rectangle on the screen where the dialog should be).
I have cut down the example as much as possible. It works flawlessly on other platforms and on Mac using Active Tcl 8.4 and the older 8.5 builds.
(Basically this issue means that currently there is *no* Active Tcl build for Mac that works with our application; almost every command-key shortcut causes Tcl/Tk to freeze.)