When it comes to variations, the C-3PO figure is the only Comics Spain figure to have a totally repainted variation or running change. The yellow figure, based on the cartoon, was the original design - the company decided to do a running change in the line and later produced an all gold version of C-3PO based on his movie appearance (sans the silver leg). Comics Spain decided to keep the eyes bright green on both versions - which would later come in handy when trying to distinguish the gold version from the Disney / Star Tours version(s).
I own another Comics Spain C-3PO that shows an example of a paint error; since these were all hand painted, errors aren't all that rare. If you take a look at both figures, the errors may not be immediately obvious, but the droid on the right actually has 5 of them. All the errors are visible from the back - starting with his head, the circle on the back of it is entirely painted gold, when only a dot should be in there. Moving down to his back, there should be a gold x across his waist, where the wires are visible, but they are not painted on this figure. The other errors are on the arms - the underarms should be painted blue (as seen with the figure on the left), the elbows should also be yellow, but in the error on the right, they were simply painted over with gold - the final error is a seemingly random gold rub of paint over the Comics Spain logo on the back of his arm.
