Repainting old shellacked wood cabinets. Cleaned with TSP and paint thinner, lightly sanded, Zinsser oil base primer, then Valspar semi gloss white. Doors have satiny finish with areas of shine. Lightly sanded and reapplied and same result. ??
You did everything correctly; cleaned, sanded, then primed. It might be a problem with the Valspar paint. Was the paint very thick/sticky or not well stirred? Unfortunately there is no way to know for sure if it is the paint or something else.
The only other idea I can think of is;
Maybe the primer wasn't completely dry when you applied the paint. Wiping down the cabinet with paint thinner would slow down the drying process of the primer. This could cause a reaction similar to what you describe. The only solution is to wait a few days and allow everything to dry/cure then apply another coat of paint.