thanks for sharing your observations.

1) Remote Buddy uses AppleScript to change channels in EyeTV. 
Depending on your system, this might be an AppleScript performance 
issue.

2) Right now, the step can't be set, but I can add such an option for 
sure. (put it on the Todo list).

3) I don't know the Zephir software, but if it allows scripting, this 
should be really easy. You can then either use the "Custom actions" 
item in the Mapping tables - or use the Behaviour Construction Kit to 
create a Behaviour compiled of AppleScripts by yourself. I recommend 
the video in the developer section of this website for a quick intro 
on how Behaviours are constructed.

Best regards, 
Felix