allready asked this earlier in other thread BUT, im downloading big file over Xolox. after downloading to ~98% (never seen more than that) it drops back to ~66%. done this allready twice, thats enough for me because over 50 hours downloading. looks like when its on 100% it drops back to ~60-70% and its very annoying. is it somekind of re-downloading because broken file (="drop and retry incorrect downloaded parts") or what?

It's caused when different segments of the download don't match. XoloX throws away one of the segments and tries to redownload it. A lot of times I've had to completely delete the file and just download it from scratch to get around this.