Below is a video I made that gives you an overview on how drawers with full extension soft close guides work, generally speaking.
The same hardware is used on roll out trays. Often understanding the anatomy of this hardware will help troubleshoot any problems you may be having with the drawer.
Above is a quick video on how the soft close drawers and roll outs from Norcraft cabinetry work... Sometimes your soft close mechanism wont work... If this is the case, it is likely because one of the guides are not engaged with the green drawer clips as shown in the video above.