Yeah, I remember. The string issue was easily fixed by simply placing a null at the end of one's strings and maintaining a Pascal string pointer for OS traps and using the C string pointer for everything expecting C strings.

I still have a work-in-progress mimeographed and hand written copy of Inside Macintosh that was used by the original 3rd party developers, back when a good 2/3rds of the OS was still being completed.