Malformed defineTile() calls lock up the engine

[BASLogin]

ToME doesn't exit gracefully if there's an error in a defineTile() call. Instead, it locks up and can only be exited via task manager (Windows). ToME reports the following error:
Lua Error: /engine/generator/map/Static.lua:142: /data/maps/vaults/forest_bas3.lua:38: '}' expected near 'add_levels'

Here is the line in question:
defineTile('1', "OLD_FLOOR", {random_filter={type="lite", add_levels=10, tome_mod="vault"}}, {random_filter={name="brecklorn", add_levels=10}})

The call looks like it is formatted correctly, so I can't make sense of the error message. Is the engine trying to tell me something else?

Also, will overload/superload functions enable me to add new vaults to existing zones? I've no idea how those work, so I've just been putting zone changes into the tome.team file as a hack.