If the interface changes to your desired language, you are in luck—your installation was a multi-language version. If the interface remains unchanged or the software throws an error, it means the necessary language resource files are missing from your installation, and a simple registry hack will not suffice.
If you search for “CorelDRAW X4 Language Pack download” on third-party websites, you will find files. However, be aware of serious risks: Corel Draw X4 Language Pack Download