We currently use very complex OMNIMARK scripts to convert LaTeX files, with math and tables, for use in the Adept Editor. The targets are Arbortext's equation editor and a slightly modified version of the CALS fragment. None of the conversions are 100% and we, invariably, end up performing a modicum of "reconstructive surgery" to obtain a usable result. However, the result IS a 100% SGML file with no LaTeXisms tainting the content. The 'work' was completed by Eric D. Freese of Information Architects (firstname.lastname@example.org) and I wholeheartedly recommend them.