Baby powder is ok , but for a few bucks you can rub in a little barrier cream from any body shop supply.
Dremel and the drum sanding fittings. Round corners for sure! Less prone to cracking. Screen spline looks great as well . Take your time. Not difficult to make it look factory. Just a little practise I guess.
Yes from a true carpenter.
I beleive you guys call it the yankee screw driver.(rubber mallot)