How to treat papers or other work from dyslexic students?
The disabilities office at my Univ (large state univ in the U.S.) strongly advises that instructors not attempt to improvise accommodations for students with disabilities, whether self-declared or documented through the disabilities office. Their point is that we (outside the disabilities office) are not at all experts in such things, in the first place. Rather, the disabilities office will discuss with faculty the possible sensible accommodations, and in effect negotiate something. Faculty should not "get creative" and take initiative.

A significant point is that, although the circumstances or environment or timing or... for exams can accommodate, there is apparently never any notion that the grading rubrics should accommodate. That is, it's absolutely not that lower standards are applied to the output, but that the situation in which the output is produced can be modified. Indeed, it is not that we expect less in such cases, after all!