Tried the local version and the only blunder given was to White after move 5 & the rest of the game played out normally. Some blunders in the code perhaps?

The tricky thing about playing locally is that white and black will always alternate- so if you're not paying close attention to the turn order at the bottom, it appears as if it is playing out as normal chess. However the turn order is five normal moves, followed by two blunder-for-opponent moves, repeating