The whole high-school angle is even more ridiculous than I suspected it would be now that I've seen it fleshed out in a script. I'm up to the part where Goku comes home from the "make out" party and finds Gohan and the two friends dead in his house. This movie is going to get a very big unintentional laugh if Wong didn't excise from his version of the script the scene where Goku marks the graves of his friends with Dragonball "trading cards," does some martial arts moves in the air over his grandpa's grave, and then recites one of the most unsettlingly hackneyed lines a person could possibly write: "I will avenge you." That sounds like something straight out of a movie used for an episode of MST3K, more Pumaman than Dragonball.
If the basic storyline of this script represents to a reasonable extent the final storyline of the movie as it stands now, then I'm guessing the screenshot of Goku bent down by a wooden floor looking sad is from the scene I discuss above. It has to be from somewhere early on in the script since he puts on the keikogi a short time later, and he is wearing regular clothes in the picture. His clothes aren't in tatters from the wolves as they are described as being in this script, but the whole confrontation with the wolves was also pretty stupid and even interfered with the flow of the plot a little bit, and if Wong has any sense about him, he should have edited that sequence out too.