The DAISY Pipeline is a free tool that can be used to convert NIMAS to EPUB. NIMAS is a subset of DAISY 3 (DTBook), and the Pipeline script is called “DTBook to EPUB 3.” The Pipeline uses this script to convert a NIMAS file to a student-ready EPUB file.
Check out this short how-to video for converting NIMAS to EPUB using the DAISY Pipeline!