Creative, but stupid.
I guess that it is possible to swab a plaster cast or scrap off a little with ease without messing up the cast. I know one field test which will give a yes or no answer for cocaine in seconds (cobalt chloride) so if customs suspect a plaster cast they could test it in a matter of minutes.
Go to jail, do not pass go , do not collect £ 200 !
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Health is a state of physical, mental and social wellbeing and not merely the absence of disease or infirmity

I am not a jigsaw, I am a free man !
Diagnosed under the DSM5 rules with autism spectrum disorder, under DSM4 psychologist said would have been AS (299.80) but I suspect that I am somewhere between 299.80 and 299.00 (Autism) under DSM4.