ToME: the Tales of Maj'Eyal

I'm in Dreadfell, and a specific vault is making a monster drop an object - if I pick it up, I get the following error, repeated every time I try to open my inventory:

Lua Error: /mod/class/Object.lua:256: attempt to compare number with boolean
At [C]:-1 __lt
At /mod/class/Object.lua:256 getDisplayColor
At /engine/ui/Inventory.lua:271 generateList
At /engine/ui/Inventory.lua:132 generate
At /engine/ui/Base.lua:90 init
At /engine/ui/Inventory.lua:56 init
At /engine/class.lua:97 new
At /mod/dialogs/ShowEquipInven.lua:72 init
At /engine/class.lua:97 new
At /engine/interface/ActorInventory.lua:251 showEquipInven
At /mod/class/Game.lua:1751
At /engine/KeyBind.lua:235

Can't send any info, as it's on a work computer.

I had the same problem.
Actually, it happened only when I opened the "jewel" tab, but I have not been able to identify the item that created it. Fixed it by suppressing the test "if self.greater_ego > 1 ..." in mod/class/Object.lua

I've had it happen in Elven Ruins. The item I picked up was a stralite ring, from the graphic, but I didn't get further than that.

Had the same thing happen, the code of the painweaver ring ego has "greater_ego = true" when it should be 1.