Dynamically updating a drop-down list within an ASD (not IaaS) blueprint

I'm trying to figure out how to automatically update a drop-down list in vCAC for a ASD blueprint (not IaaS blueprint). I looked at the Property Dictionary but it seems that only the IaaS blueprints can use the Property Dictionary, not the ASD blueprints. I've also looked at somehow updating the corresponding vCO flows input parameter dynamically in hopes that I could import it into vCAC as a list. Has anyone had any luck with this? Is there a way to integrate a Property Definition into the ASD blueprints? If so how? Google isn't really helping, it seems there are a lot people who have done this with IaaS but ASD. TIA.