Sorry, I have not dug around the forms for the answers how ever at the time we did scours the books.
1. Would an elusive creature get hindered by Mangler Caltrops?
(we played as though yes they would because, elusive only said creature doesn't hinder and nothing about conjuration)
2. Would the rings that +X to elemental damage (i.e. Dawnbreaker Ring) add to the effect roll of elemental attack(i.e. Pillar Of Light) as well?
~ On Page 26 damage Modifiers, intuitively if you cast an elements stronger this would add the to effect roll just as if the target had +X to the element (i.e. Light)? (we played for the time being as no, going with the whole book doesn't say it doesn't happen).
3. Does a Bloodthirsty creature get by the guard.
~ Again book didn't say so we played it as no but, intuitively doesn't care if the guard jump in the way or not he wants the blood of the dieing.
TY for your time.