First, I would suggest creating a virtual host record IN WAMP so that you can maintain good practices and can have multiple test domains set up for whatever purpose you choose.
flarumchina.dev would be best to start with by created a folder with that name in your www directory and then creating a vhost record to point to that folder and make changes to your host file (WAMP can add the DNS record for you as it suggests restarting your DNS (There's an option for that in the tools menu)).
Second, check your Flarum config.php file to see the url line is correct. The folder you installed Flarum in will be what you need to have the URL set as e.g. http://localhost/FlarumChina-0.1.0-beta.7b.
Your config file should look like this (unless you set an alias or created a vhost record)
<?php return array (
'debug' => false,
'database' =>
array (
'driver' => 'mysql',
'host' => 'localhostdev',
'database' => 'fbeta7',
'username' => 'dev',
'password' => 'whatpassword',
'charset' => 'utf8mb4',
'collation' => 'utf8mb4_unicode_ci',
'prefix' => '',
'port' => '3306',
'strict' => false,
),
'url' => 'http://localhost/FlarumChina-0.1.0-beta.7b',
'paths' =>
array (
'api' => 'api',
'admin' => 'admin',
),
);