Hello, I have a more than 10 years experience developping specially in FreeDOS and MsDos using mostly DJGPP and nasm/yasm compiler. In fact I'm the developper of the DUGL library [login to view URL] and i worked in this library for long years,
on the document you didn't specified how to set CS, DS, ES segments ? I guess that the function that will install the routine should provide their values.