I have also had some fasteners come loose and fall out. First, before the glue and sticks approach, check if the fastener is shorter than it can be. I found that the 5/8 long screws holding the doors on the roof lockers can be 3/4. This fixed the problem as they drew up nice and tight. Also beware of power drivers that can easily strip out the screws. Sometimes doing things by hand is stil the best way.
Bill & Martha
2011 25 Flying Cloud #525456
2010 F150 Lariat SCAB, 5.4L, 3.55:1