Yes for safespot it should be the F6 hotkey which sets the safespot to your current tile and it will be highlighted in green after it's set, it will stay in that tile unless instructed otherwise. If you want to loot everything and then return back to safespot, there is an option for it in the misc.2 tab.
As for AFK mode I will add a warning, so sorry guys if you missed any loot in afk mode, should I add an exception for highly valued loot? I have an epic idea in mind for this one.
Slayer script - first I am trying to make this script support slayer monsters without actually doing the slayer skill, only fighting npcs, then maybe I will get into a scripter team to do a slayer script, not sure just yet, seems the logical way to handle it.
Also, will be adding an update for cannon + looting, it seems the script is ignoring loot during cannon mode, should be fixed in the upcoming update too.
As for trials activated good luck guys.