Game Version

okay, so i wanted to change my game version to a different one, and when i went to create it, i hit "New Installation" named it and selected the icon, but when i went to select the version, i clicked it and nothing happened.everything else works, other versions that i have made already work, but i cant add a new one! this is really impacting my gameplay because i cant add any versions to play on specific servers and such. please help and fix this bug, if its something wrong with my launcher then please give me a sulution. i've tried a bunch of things, and i really dont wanna have to uninstall it.