I solved my uploading issue by deleting a ton of unfinished liveries from within the livery editor. No warning that I should, just figured I might have too many liveries... When I did that I was able to finally upload and share my liveries. Before that, I was unable to save liveries as well, quite the pain when you spend hours making something just to find out you can't save it!!!
I know someone else who has lost the ability to edit all his old liveries, but they are all still in his library...? but he got a message that his save data was corrupted...