A Question/Observation re Mana Shield

[Phredreeke]

I always thought that scrolls use the spell level of the currently selected spell. So if you use a scroll as an item, with another spell selected in the "spellbox", you'll get the slvl of that spell. I am unsure about how character skills (Repair, Disarm Trap and Recharge) affects, but I recall they count as slvl 15(20?).