sadly everyone does.
Hard to say, but I suspect bigger QR codes are a more sure thing for the camera to read.
Yes, if engraving. PG material is fairly the same on both side, so you can also flip it over and just manually tell the glowforge that you’re using that material.
Beyond that, unmasking materials is generally the way to go if engraving anything with fine details (vary power or 3d engrave setting in particular). The masking blocks a bit too much laser to get really great results in those cases.
In case you don’t know, GF staff doesn’t read the forum, so to an extent we’re only guessing at questions like “why is the label so large”. if you need direct info from GF, email them at support@glowforge.com.
Also since you’re new – you might like this post, it has all kinds of good info for people who are starting up:
Welcome to the club, we love new people and new ideas around here!