RGB Converter Issues

[HaRuMaN]

So I am building a bartop, using an R-Type II pcb and LCD screen. 

I picked up a Gonbes converter, like this:  http://www.ebay.com/itm/180833084570

I've had good luck with these in the past. 

Now, when I hook the board up and connect to the monitor via VGA, I get a picture, but it jumps up and down vertically, enough to make it unplayable.

I also have one of these boards :  http://www.ebay.com/itm/260868532793

It outputs composite and S-video.  Now, with these signals, the picture is stable, but the bottom part of the picture is cut off (which is needed for R-Type II).

I've hooked up a JROK sync cleaner and it didn't help.

Any other ideas?