1. If we needed to check if someone has a license, in the first instance we would just ask nicely to see some proof or something. Often we don't really need to, though. Either we already have an inkling who has it (because this is a very close-knit community) or sometimes people just come and tell us when they're using our stuff anyway! (we love to see our fonts being used)
2. Yes you can. We periodically add all of our new fonts to the pack (the last time we did so was September 4th) so even if you find a newer font on dafont or fontspace, it just means we haven't gotten around to putting it in the pack yet and you can just go ahead and use it.
3. Yes, see above. (Unless we release a font and explicitly state that's it's not for commercial use or something. But this literally only applies to like 3 fonts we've released in the last 10 years,)
