MIDNIGHT ASSEMBLY SYSTEM by Matthew Montchalin is an assembly language development package for the Commodore 128 that supports the 17xx RAM Expansion units.  Here is some info I found on how to load and run the program, but I am unable to find any other documentation.  If you have the manual or docs and would like to share, please reach out via the "Contact Us" button on the menu bar.

• Executes from either Bank 0 or Bank 1 and generates code into the Bank that is opposite the one that it resides in.
• Supports the Commdore 1750 REU with its own built-in RAMDOS, complete with commands for automatically transferring entrire batches of files to and from the 1750 REU.
• How to Load MAS into Bank 1: BLOAD"MAS-128 W*",B1
• Then execute it by typing: BANK 1 : SYS 5888
• To restore the screen editor, press CTRL + RESTORE simultaneously.
• To remove offending tab settings, press CTRL + L at the appropriate place.
• To establish new tab settings, press CTRL + K at the appropriate pave.
• For a Cold RESET, press ESC + RESTORE.