Yep like many other tilt-and-turn gearboxes mine had fractured. I removed and greased as many moving parts as I could and spray-lubed everywhere else. The replacement gearbox took a bit of fiddling and lots of grease to get back onto the rail part but was relatively simple to fit. Be sure to line the gear mechanism correctly to engage the handle at the right angle. The pvc needed some shaping with a file due to the poor original fabrication of the window. The window is now fixed and working.