Sorry about the issues you have had. It is too bad we could not make a quick call to work as I was on the road for most of the last 3 weeks.
It appears your issues with lines are not entirely related to FEP vat because the lines are there with PDMS vat as well and then it disappears. Base on the consistency of it and how it went away, it is likely electronics and has to do with environment interference. I included extra power board when I shipped you last time. If this happens again, please swap the power board.
On the FEP vat, the film initial shipped was not as great as we like. It gets punctured more easily and sometimes requires higher pm reset distance to separate cleanly. We have since found a more durable and stiffer film and got great feedback on it. We have offered that free 1 for 1 in our public post to anyone who buys it before a date in Sep and you certainly qualify.
The hitemp resin is a puzzling case for us. We have users who raved about it and completely switched to it and quite a few of them are model makers. And then some users have had issues printing with it. You could check with Evan Morgan, John Chen and others in the FB group who are very reputable and are all on hitemp and well known in the community and @Leonardo @matt3o who has accumulated a lot of experience with it. We have narrowed down to most likely factors to 3:
- printing temperature >=30C
- how supports/bases are set up.
- flesh tone resin is related to white color resin and those are typically harder to print than translucent resin colors like blue, red and green. The short reason is that light solid color reflects off UV light and takes more energy to fully cured a section. This would make some support/base design that would work in blue/red/green that might not work for solid black/grey/white.
The ideal support for laser SLA is very thick beams but less dense than how many software is generating. And thicker base as well. I am going to address factor 2/3 via Asura software and 1 via heater with built-in sensor. I am not saying your issue is related to the above factors as I am sharing what we found. It is highly unlikely that resin itself is faulty because all are mixed in one giant container before putting into each bottle. It has to be intentional to even make one bottle of resin different than another bottle if they are from the same batch.
At the end of the day, getting you back to good printing results is the main goal. I will reach privately to see what to go from this point on for you as Brazil is harder to ship than most other places. @bendouglas86 , please reach out to me on support too.