I did it. I cut, I sewn, I ironed. I, however, did not use a walking foot. And I regreted a lot.
Huge mistake. I have no ideea how I could possibly think that the silence of a regular foot could do more good than the noisy and annoying walking foot.
I will come back with more details, 'cause this quilt has such a long story, but tommorow we're leaving town and I really wanna quilt this tonight. Gotta go :)
Later edit: Do not, I repeat, do not attemp to fix your walking foot by yourself. Do not unscrew your walking foot. If you do, please let me know where the smallest L part belongs.