bkushner Yes, just set the Seestar down on measured flat and level surface. This may be the biggest challenge, finding a properly level surface somewhere. My 3d printer bed was the most level and I could shim the printer legs to get it perfect. Can use a calibrated bubble level or a good level app on the phone, but make sure it's not resting on the camera bulge. Then do the Level Sensor Calibration (sometimes 2-3 times in a row helps). Now you can immediately double check this by going to Adjust Level and it should read 0.0 or 0.1. Now gently rotate the whole Seestar unit 180 degrees on the level surface, and verify that it's still within about 0.1-.2 degree of level. If changed a lot then it probably wasn't a level surface. Double check that and repeat the process. If you can't get this part to ever work then it'll never work correctly on the tripod either and may indicate a defect. I verified on mine that it stayed within .1-.2 degrees of level through a full rotation.
Once you have verified it's level on your level surface, put it on the tripod and adjust it to as close to 0 as you can get (I rarely get to less than .2), then enter scenery mode, and quickly pan it around 180 degrees and it should remain within .1-.2 of where it was before. Yes all these errors can add up, but it's basically the best we can do. I have one of the CAVIX Tripod leveler bases, with the three thumb knobs. Best to do that part of the levelling with your body, mobile device and Seestar all lined up the same direction (forward with lights on the right).
Just to throw a monkey wrench into the works, the level sensor (accelerometer in the IMU) is sometimes sensitive to large temperature swings and will lose its calibration, but they try to mitigate this somewhat by putting it in a location inside that is warmed by the electronics to above ambient, but it may still be a factor if you go from a warm house/car to a very cold outdoors. If this happens will need to recalibrate in the field, after it's been on for a little while (to reach operating temperature). I need to run some tests on whether this is real issue.
The alternate approach, is just to put the Seestar down such that forward direction is pointing at your target, adjust level, and figure it'll be ok for the few degrees of rotation it'll need when finding its target. The further it has to rotate to find its target, the greater the effect of an out of calibration level sensor.