My bathroom sink won't drain UNLESS I close the drain while I start the water running. When the sink is almost full of water, I open the drain, I hear an air pocket dislodge, and then the sink drains just fine-- quickly, smoothly, no gurgling -- it drains fine AFTER I first close the drain...

I hung the unpainted door in the track so I could check its travel and to have a convenient way to hold it for painting. It "snapped into" the wheel hanger assemblies. Now I want to remove the door so I can do the drywall. I've "unlocked" the white locking tabs on the hanger plates mounted on...