[SlashEMDS] Special level load failure

[DeMatt]

Certain special levels fail to load properly, spamming the screen (and PANICLOG) with get_location out of bounds messages, then panic-saving and shutting down. Loading the resultant save usually results in much oddities, such as dart traps every few squares, non-functional stairs, drawbridges, etc.

The only special level I can definitively identify as causing problems is the Grotto variant of Minetown. I suspect that all variants of the second level of Sokoban are also similarly bugged, but since I tend not to reach them, I can't be certain of it. I can't say whether any special levels beyond the Oracle are bugged, either, although I will note that other Minetown variants work, and the Mall (main dungeon, between Gnomish Mines and Oracle) works.

Let me know if you want a bugged savegame from e.g. Grotto.