The only thing I gotta say, is - and I know I'll be 'filleted-alive' for this, but - this thing, imo, is NOT a 'safe' product,
as-is, as a CONSUMER product... sorry, but this:

... imo, is NOT ADEQUATE for a product that, '5
phillips-head-screws and a small-piece of gaff-tape over a micro switch-later', you've got 24 friggin WATTS of fairly-tightly collimated laser-output comin-out...
...at LEAST, (imo) they should have had a small 'optical pick-off > sensor' - heck, even a strategically-placed sensor, picking-up on just-enough-of all the
'ambient' inside this thing,
tied-in with the Interlock circuit... and/or using, like, 'rivets' on the access-door - what reason would a *normal consumer* NEED to get into that compartment, but-for a service-tech?
(...and us 
....
..Sorry, but I can't see how this got worked-around, COMPLIANTLY, with the IEC-standard...I just cannot-believe that they (Casio) SHOWED, and/or the FDA inspector who 'signed-off' on this, ever
saw THIS, which we've all-seen, blah, blah, etc...