Gliders can adapt to varying temperatures providing they are acclimatised slowly.
Best thing is to get your glider a friend as they do better in the colder weather with a friend to cuddle up with. A nestbox is much more advisable than a pouch outdoors but fill it full of fleece strips when it's colder.
Heat during the day is more of an issue than cold actually and you have to monitor them with this, though as they sleep during the day, there is no reason you could not keep them indoors during the day and let them into the outdoor area at night to play.
Also an airlock is a very good idea to prevent any escapes and for peace of mind.