thanks for asking.

Regarding your questions:

1) Your observation is right. The Remote Buddy menu and menus created 
by AppleScript use different handlers to drive the menu (it's in fact 
more complex than that, but in essence, this is right). I have 
forgotten to add accelleration support to the AppleScript handler. 
I'll add that.

2) Good question. As menu handling is different from within actions 
(=> you call the menu command - and your handler is called upon 
return) than from outside of Remote Buddy, I'm not sure whether this 
"recursion" inside actions will work.

If it does not, you can still work around it by storing the selection 
value you want to use in temporary storage using the respective 
AppleScript commands of Remote Buddy, then - from inside the handler 
- make Remote Buddy execute your action using its action unique 
identifier (both things - triggering execution and retrieving the 
action unique identifiers - can be done via AppleScript).

However, this is probably overly complex. And it would still not give 
you accelleration support, as the handler driving the menu is still 
the same.

Btw, you could completely replace Remote Buddy's menu with your own 
AppleScript by

1) Creating an action triggering your AppleScript and checking its 
"global" checkbox in Behaviour Construction Kit.

2) Replace the "Open Remote Buddy menu" action with the action (found 
in category "Miscellaneous" in the popup)

Best regards, 
Felix