First you need to download the realm.reg to register list of realms https://ingame.ro/applications/core/interface/file/attachment.php?id=209
Execute it. Then you can start to launch War3.
IMPORTANT: Realms are no longer accessible with patch 1.27b, you must return to patch 1.27a or 1.26 in order to create account
Register account through the game and not from their/our web
1. Launch the game using w3l.exe
2. Choose a gateway then login to bnet. This step needs to be done only once
3. Create account and follow whatever instruction that follows : username/pw/email, etc
4. Scroll down in order to valid the agreement then start creating account. Then you can play immediately or use ingame gproxy to play
5. You need to login for the first time the normal way, without gproxy first because the server will ask you to register your email. Then you can configure your gproxy realms and version etc..