Question: Can the playable (MIDI) keyboard range of a program be limited?

[kraut90]

I want to split two programs on the same midi channel by filtering the incoming MIDI notes range per program.
First I tried using the "Program Bounds" fields in the group editor, with no success (they seem to be invented for s.th. completely different).
Then I tried the "Key Switch" Key Lo/Hi fields - again, no effect on the playable range.
I know I could edit the regions to achieve this, but this feels a little bit intrusive.
I ended up in using two different MIDI Channels for the programs and implementing the split in the VST Host application.

Is there anything I missed, or can this be done more easily?