I'm not quite sure how save games work - I click on a spare slot and it opens it up for entering text, but there's no button to commit the save.
And what does "upload" mean?
Type in the savegame name and press Enter, it will save the game.
The upload button was a side feature with which you could upload your savegame to our server and download to another machine if you wanted. It was underutilized and misleading, so we may remove that in the future.
2.6 will come with a re-designed UI where this interface is much cleaner.
-geever