curses (and astral projection) not casting properly

I have a problem where I cast the curse, the animation plays, the mana is consumed but the curse never appears.

After trying quite a bit the probleme seems to have to do with line os sight: to cast the curse the casting point need to be in los (otherwise there is no reaction, nothing happens) but if the character moves during the cast so the point is not in sight anymore the casting fails but the mana is still consumed.

This is espacialy bad in tight spaces.


Edit: after furtther testing, the same thing happens with astral projection.

Edit2: The probleme can also happen without moving by casting at the edge of los. This does scale with area of effect: there are position where I can cast a low level curse but not a high levle one.

This also works when casting inside some pillars and behind short pillars.