Flat rafts and/or Supports stop printing. 

Problem: Z-Offset is off causing layer compression. 

This means that the very first layer being printed is too close to the LCD and there is not enough room for all the layers to be correctly printed. This is mostly an issue when printing the raft due to the larger cross section and extra heat generated by curing the raft.

Why does it affect the supports?

1. Short answer, I’m still investigating to confirm the root cause.
2. Long answer. I believe it’s because the FEP is pushed into the LCD with too much force causing very bad things to happen.
   1. The rest is pushed out of the way making for a bad cure.
   2. The FEP being pushed against the LCD will stick causing it not to release correctly creating a stuck layer that will cause a failure.
   3. Supports are more likely to have this issue due to their cradle nature when compared to a thicker object like a model. See the BLUE area. 
   4. This will decrease the life of your FEP, SCREW and LCD due to the extra pressure.
      

Fix: See Build Plate Calibration in this guide for the instruction to set your Z-Offset and check your level.