This book/software package is worth its weight in gold if you are writing programs for the 95LX.
Undocumented DOS is filled with tools that will help you fathom the depths of SYSMGR.
One gem is called INTERSPY, a TSR+scripting language that lets you compile a report of any and all DOS functions and interrupts during program execution without modifying code. The results can even be conditionally acted upon to produce a complete picture.
The author is Andrew Schulman and the publisher is Addison--Wesley. I bought my copy at Frys in Palo Alto. There are many other useful tools. If you try it please share your results here.
Mark Scardina
CompuServe ID: [71551,467]