Have you tried simply replacing the wheat flour with a gluten free version flour? There are many out there to try. Just remember to make sure the GF flour has Xanthan gum, or add additional Xanthan gum, as that will act as the missing gluten from wheat flour, that acts as glue.
I also am a "gluten free" person... but since I don't eat my gingerbread creations, I don't really worry about making my gingerbread display gluten free.
Hope this helps.
