> Here I can at least save the STLs and reprint the stuff as needed.

Until the license is revoked, changed, or you ever do some for profit work from the space where the multiboard exists. Multiboard legally owns the objects you printed on your printer with filament you paid for, so you will still be a pirate!

Multiboard is supposedly HSW compatible though so consider only printing HSW parts so you are not locked into their doomed ecosystem.