I am having problems with the UDP mode. After about 10 layers, the print will begin to fail and the part will separate. 

My theory is that UDP mode only works with small cross-sections. I think during UDP mode, when the platform raises to the next layer, sometimes there isn’t enough time for the resin to fill in the gap between the cured part and the VAT. And when the curing begins and it basically cures nothing, and then it goes to the next level.  

Can someone validate this theory? Have you printed in UDP mode successfully and can you show us a picture of the print and also the settings?