my patio door to my deck has a screened door ( sliding ). it keeps coming off track. i noticed one of the roller wheels was broken, so i bought 4 new ones and replaced them all. the door would hardly move, then i realized the long screws that hold wheels are adjustable. do they need adjusted independantly, or does the wheel at the top affect the wheel directly below it, or do they work diagonally, etc?? also, im assuming the bottom wheels ride between the two ridges, correct? but there is a groove in each wheel! im not sure what to do. THANKS for any help mojo

Any information on Posey's would be helpful!