export snapshot

[hh]

Tested to work here in LC 9.0.0-dp1 on

MacOS 10.12.1
Win 7/10
Linux (Mint173)

on mouseUp
   put specialfolderPath(home)&"/test.png" into sph
   export snapshot from img "test" to file sph as PNG
end mouseUp

So you could test whether you have write permission in the
folder where you wish to write to.