Re: Starving out a package in a Warre!!!
If you put a jar feeder using a canning jar and typical 2-part canning lid (with holes), the lid is recessed when installed normally. If you put that over a screen, the bees may not be able to get close enough to the recessed lid to be able to take syrup. Reversing the lid so the recess is inverted (now protruding) should solve that problem. The rubber seal will then be on the wrong side, so make sure the jar doesn't leak.
One piece lids may not have that recess, so that may be an alternative if you have one piece lids available. Or use the jar somewhere other than sitting on the screen.
-- Victor Hugo -- "Common sense is in spite of, not the result of, education.”