A custom skin is a modification for characters, maps, sounds and more in League of Legends.

No it’s not. Riot’s only statement for this is they put “Custom Skins” in the category “Use-At-Your-Own-Risk”.
There were no bans yet for custom skin related programs.
You can find more info about it here: https://killerskins.com/thekillerey/infos/are-custom-skins-bannable-or-not/

No. Only you can see your custom skins.

Yes you can. There is no difference between ranked / normals or practice tool.

Yes, otherwise the mods will be not loaded.

Depends on the custom skin you are using. Most champion skins replace the base skin, but you will have to read the actual post, it will say under “Skin Infos” which skin it replaces.

Yes, as long as they don’t replace the same files, for example you can’t have 2 HUD mods installed at once, but you can use a custom skins for Yasuo and Evelynn in the same game.

Yes, .fantome is both for Fantome and LCS-Manager, as they use the same way of installing skins.

This only happens when:

1. The program is not working right now and needs a fix.
2. The mod you are using is not updated for this patch yet.
3. Your mod has an incorrect .wad.client name (they are case sensitive!).
4. League changed up its game files.

Check this post for more in-depth help or ask for help on our Discord server.

Normally yes. Make sure you are using the latest versions of either program and check the #announcements channel in our Discord-server to get information about program functionality.
Our frontpage also states the current status of custom skin programs.

Make sure to check Error fixes or #error-fixes in Discord for more in-depth troubleshooting.

You can also ask for help here: Discord

Wooxy is no longer used for installing custom skins and no longer able to.
You can still use features of the program. You can download it here: Wooxy.
It might trigger your Antivirus, but it is a false positive and not a virus.

Yes, but you will need to update them: https://killerskins.com/yoru/tutorials/updating-old-wooxy-skins/.

The website got shut due to hosting issues, we fully transferred over to Killerskins, the same admins and members are still around and old skins were recovered or will be reuploaded.

The owner shut it down due to inactivity as custom skins back then were not possible to use for a while.
Old skins were recovered.

It got shut down due to inactivity most likely, but nobody in this community was really involved in it.
Some skins were recovered.