Is there a way to convert old kits data to new? It's very hard to re add if you have more than 100 kits (Bots, Arena).

read the documentation. there is a command that does it 

do kits.convertolddata in you're Rcon console no ingame console

And good luck with it, with only 30+ kits i am now in the process of trying to re edit them all as the new version does not recognise my inventory clothing.
you will have to (probably) redeem each kit and be prepared for spammed message in console stating that it cannot download the "forbidden" image each time you edit a kit. and even though with the gui which shows the kit is hidden/auth2/admin you can still claim it (and edit it) with no permissions

It works thank you guys.

pookins

And good luck with it, with only 30+ kits i am now in the process of trying to re edit them all as the new version does not recognise my inventory clothing.
you will have to (probably) redeem each kit and be prepared for spammed message in console stating that it cannot download the "forbidden" image each time you edit a kit. and even though with the gui which shows the kit is hidden/auth2/admin you can still claim it (and edit it) with no permissions

Covfefe

Now I'm afraid to update

It works after the update and you can only see or redeem the kits you have the authlevel for , But i still get the error message in console as Imagelibrary does not recognise my inventory (no workshop) clothing,