Which Red Button do you mean. The record button? The Harmony One is a remote that is capable of emulating a lot of different remotes and can put together different button presses into a series (marco). Also which plugin are you using for your iMON receiver?
Right now, eventghost is handling the IR signals that are coming in to your iMON receiver. That IR signal needs to be linked with a an action within mediaportal. This is what eventghost is doing. I think that it is a little more complicated than just ticking the General HID button in the configuration but I could be wrong. So 1) mediaportal needs to be able to listen to your iMON receiver (which it might do but this is what eventghost is doing) and 2) it needs to know what to do with the ir signal (map the ir inputs) and 3) the signal that your harmony one is sending isn't a "Harmony" specific signal it is likely a iMON or WMC signal.
I know that this does not help a lot but hopefully it will help get you to where you want to go.
Right now, eventghost is handling the IR signals that are coming in to your iMON receiver. That IR signal needs to be linked with a an action within mediaportal. This is what eventghost is doing. I think that it is a little more complicated than just ticking the General HID button in the configuration but I could be wrong. So 1) mediaportal needs to be able to listen to your iMON receiver (which it might do but this is what eventghost is doing) and 2) it needs to know what to do with the ir signal (map the ir inputs) and 3) the signal that your harmony one is sending isn't a "Harmony" specific signal it is likely a iMON or WMC signal.
I know that this does not help a lot but hopefully it will help get you to where you want to go.