I've tried to fix all the crashing - basically it happens anytime the "world" changes (e.g. we enter a portal, click the boss accept button, use a banner, take a town portal, etc).
I believe with the most recent version of Trinity and QuestTools, we've fixed all the crashes - I haven't personally had any in quite a while. I keep looking for (and finding) places where this can happen, so, bear with me.
Hopefully at least the crashes have stopped?
Also, since it happens every 20 minutes, maybe you can watch your bots and see exactly what they're doing when it crashes?
Logs are good too...