Arkham development has re-implemented Amiga-support in their antiryad 3d-engine. I have not tried it myself yet but they said so in a mail. So perhaps you should check it out :
http://pyro.akm.free.fr/html/antiryadgx.htmI don't really know where to find the amiga-version but there is supposed to be one. Perhaps it is included in the package. Ill try it as soon as I get a new modem for my Amiga. Anyways, perhaps someone can make use of it. Its an excellent engine.