Even here a charged ML without a cap is considered unloaded Ha, what do you know, and that in Canada 
Same here in Virginia, USA.
1&2 - I leave mine loaded until the end of the season, of course they are loaded after each shot!

3 - Better check on that one. I have heard that some dealers do require a back ground check on MZs.
As far as the ATF is concerened, I have heard both ways as to if it is a firearm or not.
4 - Again, some dealers do require it, a private person may ask for an ID but it's not required here in VA.
If in doubt, check with your local gun shop, they will know for sure on #s 3&4.
LONGTOM