Do you see a brick wall at bottom left of LW's main window?



Some basic questions first: Check how many upload slots you have. Do you have LW set to share partial downloads? Do you share files immediately upon completion?

Sometimes whilst actually looking at LW you may not see any uploads. There are other ways of knowing if uploads have happened. Example, check Library window, check your shared folder, the columns Hits means those files were found in searches, your uploads column means a/b .. a = successful uploads for that file, ... b = either incomplete/partial upload or broken upload attempt (which may or may not mean they finished the upload via another user sharing same file.)