I notice that my prints are very "tacky" several days after coating.

Dilute more. If you dilute less than 30% with water, the more likely this is to happen. If you are diluting with 30% already, try 40% or even 50% to reduce tackiness. Make sure the coating has completely dried and is no longer sticky before storing prints face-to-face or putting them behind a temporary frame that you ultimately intend to remove. Also try using a thinner coat. If you are using too much product, this could happen.