Contact the addon developer by help of a private message and tell him/her what you need to have updated.
Maybe he/she wil limplement it.
If only the API version needs an update because it shows "out of date" ingame, simply edit the addon's manifest txt file and change the line here to the most current api version
Code:
## APIVersion: 100017
Save the file and reload the game.
You can get the most current api version by typing this into your game's chat box:
Code:
/script GetAPIVersion()
If the addon is not working afterwards you need to learn lua and fix it yourself or let the addon developer do this on his own. Assist him/her by providing information via PM or comment to test and find the errors.