On getting the Vat to remove or redraw the resin… Here’s a tip…
Get a plastic spatula with a clean edge. You should have one anyway. NEVER use a metal or sharp edge on the polymer film in the vat! NEVER push HARD down when you try to remove a stuck bit. Better to drain the vat and lift it and lightly push from the other side with a gloved finger tip to get it to come off.
While the resin is redrawing sweep the stuff towards the resin tube and make it deep around the tube. I find it takes less then 5 min when I do it this way. It’s a good practice since you do need to inspect the polymer carefully for left over stuff stuck to it after every print. You also HAVE to sift through the resin to make sure there’s no floating pieces. You do not want them drawn into the tube!
If you have an FDM 3d Printer (which you should) you can make a sifter… Here’s one I made and posted to the Thingiverse:https://www.thingiverse.com/thing:2377792