1) The only way you can get a controller keyboard to change the mode of the X5DR from program or multi to combi is through system exclusive messages. The A33 cannot be programmed to transmit the sequence required to change the mode.

2) You can only use programs in MULTI mode.
The module will receive messages in the combi mode, if they are on the correct MIDI channel. Each part of every combination is set as to the MIDI channel it will receive on. The factory Combis all receive on channel 1. If you set your A33 to transmit on channel 1, and the wave/4 is set to simply pass through the message without 'channelizing' it, it will work.

Steve Martin
Ward Music Ltd.