I'm thinking if you see something and draft your own interpretation of it, knowing it's not a copy, that's not a violation. However, if you take a picture, and make yours just like it, or only move a thing or two around, that's infringement. It's about making something that looks just like someone else's work and taking credit for it as your own. Think plagiarism. Either quote and give credit, or rearrange the ideas in your own words. :-)
If I remember I saw something and I liked how the blocks looked and make my own version of those blocks in my own setting, using my own technique, without making it exactly the same, that's not making an unauthorized copy.
It's kinda like the ladies who go to a store and see a dress they like and go home and design one like it for a lot less than, say, $600...it's their creation, and it's not a piece by piece copy, so it's cool. :mrgreen:
Trisha in MO