http://www.modelaircraft.org/PDF-files/510-A.pdf lists the turbine-specific safety requirements from the AMA. This is in addition to the rules that apply to ALL models regardless of powerplant type.

You could probably also contact Carl Maroney and / or Ilona Maine at the AMA (see http://www.modelaircraft.org/maildir.asp for contact info) for hints & tips about any specific turbine-related issues that were "red flags" in obtaining insurance coverage.

Gordon