Xbox 360 Live games - Gold Live license necessary?

All online games require gold.

Shouldn't need to try it. The games work the same way - a console license and a gamertag license. The first console to download the game on the 360 side gets the console license. The purchasing gamertag's "home" console on the Xbox One side gets the console
license. As long as the 360 gamertags have Live Gold the game will work on the 360 side. Xbox One "home" consoles can share Gold so it shouldn't be required on the Xbox One side.

Depending on where you purchased the original 360 copies, you need to return the physical 360 copies to those locations for the $10 Xbox One values. If you purchased them digitally through the Xbox Live Marketplace, you already have the necessary licenses
to repurchase them on the Xbox One Live Marketplace for an additional $10. To answer your final question, you will be able to to use both licenses - 360 and ONE - at all times. This means if you bought Ghosts on 360, and subsequently upgrade to One, you will
still be able to play that game on 360.

Do you still have an Xbox live gold subscription?

To continue to have the license to play the Xbox One games It is required to keep a gold subscription active on the account. And NO sharing a gold subscription with another profile does not work.

The 360 games are not affected by the gold subscription requirement.

Once you renew the gold subscription you will gain access back to the licenses for the Xbox One Games with Gold.

the problem is the maintenance of the servers so if necessary the xbox live gold