I just purchased a Beomedia 1 and before hooking it up to my main system I tested it without any problem using a computer monitor/VGA cable. However, when I connected it to my Beosystem 1 ,I do not get any picture on my Pioneer Plasma. I followed the instruction manual which recommends to use a S-Video cable from the BM1 connected to the BS1 V.AUX Input. The BS1 is connected to the Pioneer plasma using a VGA cable. I do receive BM1 sound and I can turn on the Beomedia with the Beo4 via the IR sensor connected to the Beosystem 1.

Is it a BM1 screen resolution set up issue or is the S-Video from the BM2 causing a problem with the VGA from the BS1 to the plasma?

Hopefully someone can help me

If you haven't already resolved this than you've got a few variables to set aside.  I would recommend a simple test to see if you can get a source  (DVD?) to play through the BS1 to establish first that you've got the BS1 set up properly to display from that input.  S-video resolution shouldn't be a factor so you if you've confirmed that the BS1 isn't the issue than I would confirm that the BM1 is outputting S-video.  I don't have a BM1 so I can't help with that but I would guess that there may be an output setting in the menu that you may want to select while attached to the computer monitor.