This is what my hinge fix looks like (I have 3 of them):
http://i658.photobucket.com/albums/u...ort-shrunk.jpg
I hope the link works.
I cut the black support to create a straight edge, then attached one side of the hinge with 4 screws/washers/nuts, then drill holes in the metal support where the other side of the support was located. 4 more screws/lock washers/nuts to attach the other side of the hinge on the frame and voila. The hinge provides the movement of the plastic support as the slide extends or retracks.
I will probably have to lube the hinge on occasion and check the torque of the hardware, but this is working for me so far. I have not seen any evidence of cracking so far.
Other members have used more substantial hardware but hopefully you get the idea.