This is a known bug! It's fixed in 0.9, which will hopefully be out by Monday, 13th June, 2022.

You should only be writing patterns to scrolls; use Consideration, then draw a pattern, then try writing it.

(Also please open a fresh issue in the future instead of commenting on this one!)

Hi, I'm playing on the fabric version of 9.0, and for some reason I'm still unable to write spells to scrolls. In fact, the game actively labels them as being unwritable with the "Auditor's Purification II" spell.

If it helps at all, this was experienced in the Blanketcon 2022 modpack. Sorry for the hassle, and I hope things go smoothly for you with this mod!