Notice this at the same time as this recent bug report: https://www.efupw.com/forums/index.php?topic=698054.0
In the Grand Fissure, connected to the interior of a cave tileset, there is a few web placeables that block a corridor to a quest giving placeable. Normally you can target these from the radial menu or simply select with a spell to bash, however there is something strange with how these are layered or placed such that PC's can't bash them. Spells start but then stop because of invalid targeting. Bash actions can't be completed.
This particular set of webs is immediately after the first room you enter (not the first corridor) once you load the area, after the first encounter with spawns.
Should be fixed.