[1.4.8]LUA error when I try to access sher'tul library

[Zeyphor]

I have embers and orcs installed, and I also use the 1.1.5 orc breeding pit restoration addon
when I try to access the sher'tul library the loading bar (presumably)indefinitely freezes at various intervals, usually 21% or between 21% and 90% or between 90-99%, and after that it never finishes
when it freezes between 90-99% I get the achievement noise, but the achievements don't pop up
when the loading bar freezes, this LUA error doesn't pop up in-game, but it does appear in te4log.txt

Lua Error: /mod/class/interface/PartyLore.lua:82: invalid value (boolean) at index 2 in table for 'concat'
At [C]:-1
At [C]:-1 render
At /mod/class/interface/PartyLore.lua:82 getLore
At /mod/class/interface/PartyLore.lua:96 learnLore
At /data/zones/shertul-fortress/grids.lua:233 check
At [string "return function(self, x, y, what, ...) local ..."]:1 checkAllEntities
At /engine/Actor.lua:209 move
At /mod/class/Actor.lua:1289 move
At /mod/class/Player.lua:300 moveDir
At /mod/class/Game.lua:1739
At /engine/KeyBind.lua:230