Have you successfully printed these (or similar) parts in durable resin before, or did the warping occur as soon as you switched to durable resin?
Last winter I went through a trial-by-fire with Tough resin, where I was having major warping issues. After several weeks of testing, where both Formlabs and my local reseller did test prints along with my own, as well as consultations with Formlabs’ material engineers, it was concluded that the Tough resin simply was not capable of producing warp-free prints of the objects I was trying to print, no matter what we did.
The same warping occurred when printing the object (as a test) in durable, but NOT in Rigid, Grey, or Grey Pro.
I have also had similar parts test-printed in Dental Model, which also produced significant warping.
If you just switched to durable and have no issues printing the parts in more stable resins, it’s probably not a direct fault with your machine, just an unfortunate limitation of the technology, which is sadly not commonly known.
The general rule seems to be that the more durable the resins are (higher longation, more flex before breakage, I think), the more prone they are to warping. If straightness and dimensional accuracy are important, you’ll probably have to go with the harder, more brittle resins.