ctrl Z use in plugin

I am demoing Tremor. In standalone mode, crtl z undoes the last entry to the step sequencer (Tremor step sequencer, not Sonars). When I run in Cakewalk, it undoes the last action, which is typically 'insert Tremor'. When I enable 'Give all keystrokes to plug-in' my system beeps at me and nothing happens. 
 
Is there something I can do to enable crtl z to work in a plug-in. After using the standalone, this action has become a little ingrained, and it's really useful.
 
Any Geist users able to chip in, as it will be the same situation I guess.

Thanks for the reply, I can't see that option in preferences or the manual. I'm guessing that was added to Giest2 and Geist1 and Tremor both have this limitation.
 
Not a massive limitation, but after using in standalone first I started to reach for CTRL Z automatically. At least with enabling the keystrokes to Tremor, it doesn't undo 'add tremor'
 
I like the step sequencer in Tremor, but Sonar's is much more flexible and complete. Shame you can't collapse the sequencer veiw in Tremor. Seems Tremor 2 is dead in the water.

There are always going to be limits on how plugins and hosts work, this whole keyboard focus thing is one of them.  Most plugins don't even have an undo concept even.
 
The option for Geist2 for extended keyboard isn't even covered in the manual (or if it is I couldn't find it) if you don't have it checked you get the beeping with ctrl-z if you give the plugin the keyboard focus in CbB.  You might want to contact FXpansion and see if they would add that to Tremor.