After applying the shine effect, the source opacity is greyed out and cannot be adjusted. In a previous thread I learned that it depends on the transfer mode selected... How do I change this mode to allow adjustment of the source opacity. Sorry for the rookie question, but hey, I'm just a rookie.
what host are you using?
normally just select any other Transfer Mode than "None" and it should be ungreyed.
Premiere Pro is a little buggy on this sometimes - if so try disable/enable the effect and see if that helps-.