thanks for your posting.

A few notes:

1) You don't seem to either compile and testdrive or export your 
Behaviour. Please see the "Simpler behaviour development" thread 
regarding that topic.

2) You shouldn't create a Behaviour of your own for an app that 
already has a Behaviour. Of course, you can, but it'll probably be 
confusing as two Behaviours for one app are 
a) concurring for the auto selection of the Behaviour 
b) turning up in the menu with the same name

3) If you want an action mapped to a button, you can do one of the 
following: 
a) declare your action global in the BCK and then select it from 
"Miscellaneous" / "Verschiedenes" in the mapping table. 
b) select "Custom actions…" in the mapping table popup and add your 
action there, so it is available in the context - and only in that 
context - of the RealPlayer Behaviour

4) Finally, if you want to have a menu item rather than an action 
mapped to a button: 
a) declare your action global in the BCK 
b) use a customized menu (menu pane in Preferences) and drag and drop 
your action from the "Miscellaneous" / "Verschiedenes" to a place of 
your choice in the menu.

Hope that helps :-)

Best regards, 
Felix