> his decision not to let anyone else have the code so that they could update the maps. ???
Yes, my understanding is it's from a legal agreement he made back when. It's reading from the data stream, and as innocent as it may be, free source code could undermine UO worse than it is now.
It's not just updating the maps, you can do that yourself, the problem is that UOAM makes (& uses) a set size map, and expects the maps in the MUL files to be a certain size, but UO made the maps in the MUL files wider and added more of them (SA), which is why it crashes now.
The UOAM executible would have to mod'd (rewritten) for both of those changes, plus there was a auto-calibration/tracking issue that was in-op. For someone that doesn't play UO, and gave the program away for free, why should he bother.
I heard a replacement was in the works, but...