Multiple solutions!? Gah. Well, there's the problem.
I checked your solution to that last one and couldn't find any problems with it either. I tried to solve it myself, working from the originals, but I ended up stuck with quite a few that I couldn't figure out without guessing. I compared them with your answers, and they're all the same -- except all the red numbers from yours are the blanks on mine.
I guess you just found a different solution that wasn't what the computer was expecting. Good job, anyway!