Bert, orange peel and fish-eyes are a common occurence when using epoxy as a coating medium (like paint). Epoxy is an adhesive not a paint, we're all using it as a paint once the fill coats are laying flat on each other. It sure has weird viscosity characteristics on the last fill coats. If you think another coat will be needed given the finish sanding to be done then let it cure, wash it, give it a rough sand with 100grit and lay another coat down. A reasonable argument is made for surface contamination but I think it's the nature of the material,,,or sun spots.