I went ahead and did a batch process in PixInsight and stretched the image (this is non linear) ...but there has been no adjustments...no crop....nada. I just registered, calibrated, and stacked the images then stretched and saved as a jpg file. But I processed this without using the insane flats.
For the record, I took 100 flats and the artifacts - debris - moisture whatever it is changed through-out the 100 pics. In other words...not two are exactly alike....close but not exact. And very noticable changes when comparing the first with the last flat.