The silkscreen was white because the dark background in Illustrator made it easier to see. Now that ILL is not free we switched to INK, unfortunately there are a lot of old parts still with white silkscreen still in FZ. The upside of changing it to black is that you can now see what the part looks like in the PCB icon in Inspector, rather than just a number of contacts.
I think those zero nodes might be a Eagle conversion - Eagle adds tons of junk -.
Ardiuno don't run a 0.100" pin spacing on all pins, so it won't fit prefboard