mamadoc - what about your ingredients? are you using real butter? something is causing the sticking - shortbread is buttery and shouldn't stick - are you preheating your oven long enough? is your oven temp also the same when using an oven thermometer? using ingredients at room temp? did you adjust your bake time? (sorrry - so many questions)
also - I don't know how thick your forms are - forms can be pretty but the thickness of them can also effect the recipe/baking
The forms are 1 to 1.25 inches thick. Always use fresh butter. Usually up to room temp., but could be slightly below. I cook until v. slightly beige on edges, and firm on top-cooked by "toothpick test. I am 58 and have baked since I was 10. Chocolate, ginger, capuccino, and almond shortbread are no problem. I have small round and square presses I use on my reg. stuff, but this floors me. Surely someone has used one of these forms, or the Scandinavian ones!