Try and

How connect to remote Bytecoin Node

Open bytecoin GUI wallet, click Tools -> Wallet Daemon Parameters,
select "external bytecoin node" and fill Host field with one of IP addresses listed on this page

How connect to remote Bytecoin node

Thats all, now you use remote node, so don`t need to download blockchain.

It`s better to download blockchain. But if you use wallet not often or haven`t enought space on your hard disk, you can use this method.