The TrueTypeViewer, TTIComp, OTComp and OTLegacy all use my easy-to-handle, fast and safe OpenType font manipulation library. You may download the sources to all of those at once. The current version is 20030318. Building the tools requires the following:

All of the programs are distributed under the GNU General Public License. I appreciate feedback (a guide to my email address). However, nowadays I am so busy doing other things that I'm unlikely to be able to act on it. The GPL allows you to redistribute changed versions, which may be an interesting option when you find problems.