There were 3 episodes lost which weren't uploaded on the official Youtube channel. The episodes were "Green Cross Code", "Marathon Man", and "Porkchop". The first two episodes mentioned were found and can be viewed on Youtube, but "Porkchop" remains unuploaded. There's no information about the episode because the show wasn't popular enough. There only remain two screenshots.
I found the "episode". It turns out it wasn't an episode but a animation for a menu select screen for the DVD of season one of Angry Kid.
Skip to 2:02 for the animation.