Good God... Finally... Though I must say, for the future generations of people not being able to use it correctly: the problem lays (in my case), if not in the files (i used yours, and substituted the files from the video above in lieu of yours) then also in the conectivity? At first there was no response (loading again), but seeing how it was a different reaction before, I tried rearranging the whole ensemble (r4 and sd, than this into the ds). And then it worked. The issue was, as far as I can tell, that the r4 was not correctly connecting. After puting a piece of thin cardboard between it ant outer layer of the port, it worked. I think that duct tape may be the correct solution longterm.
I'd like to thank You all for wonderfull support along this wild ride.