Notes:
1. To prevent screwing up your client, change your system locale to Chinese, Simplified before installing TGP. Tencent Games TenProtect program will encounter multiple problems with applocale.
2. TGP is recommended since most players will be non-CN locals. TGP will help boost your connection to the game by re-routing through a more efficient route, reducing the ping to the server.
3. If you have other boosters and want to download the game via other methods, go to
http://mho.qq.com/download.shtml and select the 3rd option from the left (green button) to download via QQ Download Accelerator via
Internet Explorer. For some reason, Google Chrome is unable to open the QQDownloader.
It's less user-friendly than MHO Downloader, but speeds up the download process by a very large margin.
Note: You might need an existing QQ account to use the Accelerator, so make sure you sign up for one beforehand.
After clicking the green button, install the QQDownload_Setup.
Click the green button again, and click the highlighted box:

Recommended: Double click the other files to pause their download. Downloading one-by-one can sometimes be faster than downloading all at once.
My current download speed:

Better than 300-400kb/s from MHO Downloader.