I finally found the answer for this. You need to make a DWG that contains nothing but the fonts you want to use in AutoCAD. Start with the ACAD.DWT as a base because it is basically empty. Once define, save the template DWG in a logical place, keeping in mind that you're going to reference it from ArchiCAD.
In ArchiCAD, in the Translator Setup, in
Save Options
you specify this DWG as the "Template File for Additional Settings". Then you go to
Attributes->Font-style conversion
and enter your style mappings.
If you are using the same True-Type font in ArchiCAD and AutoCAD (ie Arial to Arial), then the conversion works great. But, if you are mapping aTrue-Type font in ArchiCAD to an SHX font in AutoCAD (ie Tahoma to archstyl.shx) then you will still see the Tahoma when you open AutoCAD.
The reason you see this is because ArchiCAD embeds font calls in all the mtext and dimension entities, so even though they may be using the right text style, the font has been changed within the entity itself. To fix this you need to download a lisp routine called StripMtext from the web. You can get it at
http://www.users.qwest.net/~sdoman
. When you run this program you can tell it to strip out the formatting and -- shazzam -- your text and dimensions use the right font.