Video Output Issue

I am using a white iMac running OSX 10.6.8.
I purchased a Mini DVI to S-Video/AV Adapter. I plugged this into my tricaster unit (Video Input 1). There is not signal being received by my tricaster. No picture. Is this a known issue or could the Mini DVI Dongle be faulty?
I have a mini dvi to vga output. That dongle does work, I have tested it. Is there a cost-effective way I can use the VGA dongle with a VGA cable and convert it to an S-Video or RCA signal?

Please help. All setup at my school. If this works, we purchase the product.

Does the system recognize the dongle as a secondary display? If so the issue might on the tricasters side. You could also get a dirt cheap adapter cable like this one to adapt from VGA to S-Video:

I have been creating a video using ipad3. While using the front camera I noticed that my videos,on play back, are reversed. I am right handed and in the video I am left handed and the background is also facing the wrong way. Is there something I am missing?