Should all of the coins be round?

Should we keep the designs only gold / silver or are we allowed to add color?

Should entrants refrain from pointing others to vote in this contest? I understand this can be a gray area, but the more clarification we can get on this the better.

Are we allowed to use some or all of a design that we submitted for the previous contest? I'm not planning to but in case someone else would like to it will be best to clarify this now.