Are you aware that FM (Frequency Modulation) is a very specific type of synthesis and not a general term for synthesized instruments? Tons of trackers in the database have FM specified as sound generator, but that is simply not true. For example, neither the NES nor the Gameboy have FM synthesis, so certainly neither NerdTracker nor Paragon's GB Tracker use FM synthesis for sound generation. "Synth" would be a more appropriate label, which you seem to use for a handful of other trackers.
On the other hand, OpenMPT does actually support FM synthesis so it would be nice if that could be added to its entry (together with the corrections posted on page 1 of this thread).
I also have to add that I find both the color scheme and the font to be rather hard to read.
