like always the proper tool is paramount. if you look at the screw slot, it is sraight walled. i.e. the slot is straight up and down on the sides, viewed from the side. most standard screwdriver blades a re tapered, like a wedge, and will "cam out" or climb out of the slot when tightened. the cure is proper srewdrivers,made for straight wall slotted standard screws. these are sold with various decriptions, including hollow ground, parallel tips, gunsmithing drivers, etc. brownells, sears, snap on,and i'm sure lots of others carry them. i also have these drivers with 3/8 drive, so i can use a ratchet to turn them.
as for the loc-tite, i remove it and use my own in liquid form.