Is there any way to roll the printer back when you’ve changed something that was working correctly?
Yes, you can download old firmware versions. When preform asks you to select your printer you can click the “update” button and manually select whichever firmware version you have on hand.
If you have trouble finding the old firmware page, this link should take you there:
https://support.formlabs.com/s/article/Firmware-Release-Notes?language=en_US