Controlling ProgDVB with WindowMessages

#1
Hi,

I am trying to (remote) control ProgDVB. I'd like to execute typical commands like play/pause, next, fastforward, etc.

I found this headerfile:
http://download.progdvb.com/tools/RcPlugin.h
And tried to send commands in C#.NET like this:

private static extern bool PostMessage(IntPtr hWnd, uint Msg, int wParam, string lParam);
...
PostMessage(handle, 0x400, 0x01023004, "Play");

It didn't work, "Exit" didn't work either.

Am I trying it the right way or is there an other, easier interface (that is enabled by default)?
Is it possible to send those commands from an external thread?
I'm not sure where to send the command (hwnd-parameter). I tried sereval ones that I found with Winspector. Can you help me to identify the "hCommandWmd"?

I'd not like to fall back to the command line if possible because that uses pretty much cpu especially when adjusting the volume 10 times per second.

I have no TV card since a) I have Vista x64 and b) my only PCI-Slot for my old tuner is blocked by a double-height graphics card. So I use online TV.

Thank you!
Greetings from Germany

Philipp