I know that a lot of people have looked into this, and so far nobody has gone "public"
on the format.
In particular, a lot of people have looked for a way to move the QCT format into say TIFF so it could be run under Oziexplorer. MM is a pretty cr*ppy GPS application really. The transfer has been done, on selected maps (non aviation), by printing to a TIFF-generating printer driver. You can download the twelve UK 1:50k O/S charts from ED2K for example, both QCT and OZF2.