ToME: the Tales of Maj'Eyal

first post, sorry if this is somewhere else.
did a quick search in case this had been reported and found nothing, so maybe its not been reported yet.

Anyway, I had gotten the corrupt shell prodigy unlocked, then I turned on the grand corruptor, because I figured, why not, I'd already gotten rid of zigur... but, then the prodigy re-locked itself. (well, I should say, it was always locked because I didn't have enough con yet, but the defeat zigur/7500 blight damage bit went back to red.)

if the grand corruptor needs to live to have this unlocked, where does it say this?
if not, it shouldn't re-lock after I kill him.

thanks.

p.s. if there's a list of commonly reported bugs somewhere, could somebody link me to it? if I'm gonna start bug reporting, I'd like some way to check that I'm not re-posting something already known.

The prodigy is designed to be locked if the corruptor is dead. The prerequisites could be more clear by stating that the corruptor must be alive.
Note that the quest to defeat Zigur is coded such that it assumes that you have betrayed him if he dies any time after Zigur falls (even from non-player damage).