GWToolset is uploading a lot of file names like https://commons.wikimedia.org/w/index.php?title=File:The_King_of_Hungary_holding_council_in_his_tent_on_the_battlefield_-_Froissart--39-s_Chronicles_-Volume_IV-_part_2-_-1470-1475--_f.84_-_BL_Harley_MS_4380.jpg&redirect=no . The proper name is [[commons:File:The King of Hungary holding council in his tent on the battlefield - Froissart's Chronicles (Volume IV, part 2) (1470-1475), f.84 - BL Harley MS 4380.jpg]] (and it has since been renamed to that)
Notice how things like ), (, ', & are being stripped and replaced with '-'. This is wrong, those characters are perfectly valid in a title.
Even worse, characters like apostraphe (') are being converted to their html entity "'", with &, # and ; being replaced with dashes, resulting in "--39-". This is wrong, as html entities in titles should be converted to the character they represent, and that character should be dealt with as appropriate (As is done in normal titles)