It's a remote to got from maplins, I've had to map the keys for mepo and the green button has never worked in mepo however, the remote works perfectly in media centre on win 7
I'm also using this combination (Mediaportal 1.1.2 and Win7) and the green button works and starts Mediaportal.
(I must admit that it didn't work immediately, but I don't remember what I did to fix this.)
Yet I'd like to report another issue:
When starting MediaPortal with the green button (in full screen mode) the window won't be activated and the task bar remains in front. Then I first have to click with the mouse somewhere before I can use the remote control again.
When I start MediaPortal via mouse then there is no such problem.
It's a remote to got from maplins, I've had to map the keys for mepo and the green button has never worked in mepo however, the remote works perfectly in media centre on win 7
AFAIK MPtray only work for the original IR remote and keyboard (and replicas using the same priciple). I have a logitech dinovo mini myself using bluetooth. MPtray does not work with the green button there either.
I think MPtray "senses" for the IR code from the MCE remote. Maybe it would be better if it could pick up the green button press in another way, but I don't know how.
If launching Media Center works with your remote you can replace ehshell.exe and use it to launch MP.