Sami,
FSUIPC is a program that was written by Peter Dowson for allowing external programs and panel gauge programs to access the data stream that fs200X is generating. It is two way...... you can not only access the data being generated,....but you can write to the data stream.
So this allows a programmer to utilize FSUIPC to not only display values or control external devices..... but also allows an external action to control what happens in the simulation. For example by writing a new value to the memory location that controls the electrical supply to say a fuel pump........ it goes "blooey". Want to fail the nose gear? Easy.
You can do more elaborite and more subtle failures than the "failure generator" that comes in the fs2004 program itself....limited by your imagination and your programming abilities.
If you can program in Visual Basic or C++ the code is not too hard to figure out. The program has an extensive SDK with it. And the stuff is being modified and upgraded all the time. There is a support forum too.
The version for FS2004 is a payware program. Versions for fs2002 and before were freeware.....but are no longer being supported. Bundled with WideFS (which runs FSUIPC across a network for the kind of thing you are thinking) the current version is about $35 USD.
The main website on FSUIPC is to be found at http://www.schiratti.com/dowson.html
There is also a new freeware product for fs2004 that does the same kind of thng.... but I don;t know all the details about that one. I think it is called FDSConnect or something like that.
A lot of what you are thinking is being done by simpit builders already. The REAL issue is can you get it approved for what you want. ;)
Hope this helps.
best,
...................john
PS: Just posted some new pix of my own simpit project down in the "Homebuild Cockpits" forum.