When i make mine i wait til the acetone is all dried up so definatley wait till after, you dont want acetone smell mixed witht the drops.
I only put 13 mg on each gram of mine and people are satisfied and you can always increase potency.
But personally i prefer just smoking jwh feebase.
I have the same exact one from ebay, and ive had it for a while and it works good for weighing JWH-018 and its been running on the same batteries. But i hear the same high pitched noise haha, ANYWAY just use the white manual they gave you to put it under one of the corners of the scale and it...