Stuck onto Kashyyyk jump flip walls

OK, folks, I'm quite close to give up.

I'm playing with keyboard (I'm not capable to use a joypad) and it seems that there is no way to overcome the jump flip walls at the top of the mega-tree.

It seems that I'm not capable to find the right timing for jump-flipping, and I can barely reach the third wall.

It seems also that It is not possible to gain height during the run, because the starting speed is too low when Cal starts running.

It is impossible to reach the third wall, I did it only two times in one hour of tries.

Figures to reach the fourth wall. For me is impossible.

Is there any other way to reach the other side of the walls ?
I know, I know, it is not beautiful to see, but is there any possibility to edit the save game to let me go ahead with the story ?

Please help.

Thank you.

Guba