Hi Zarko, good to meet you, I may have missed your earlier posts, did you brine your Gouda?
4 days seems long for a cheese to dry it's rind (edit: meant to say 4 days is long to leave at room temp, continue drying in cheese cave where the humidity is controlled ). I don't think I would leave it longer at room temperature. Was it always "sticky" ? I believe waxing is the easiest idea... traditional too.