Hi, Phil. Acetone is the solvent for ACC glue/Crazy Glue, but I have no idea what it will do to the Corian. You might test by rubbing a rag with acetone on the bottom of your countertop and checking to see if it reacts. If it does, your best bet might be an X-Acto knife. This will scratch the surface but if you are careful, the scratches should not be too bad. A pro should be able to polish the scratches so you might be just as well off to call your installer back and let him do it.