The role of Light.exe

Light is the tool that links your .wxl files with the .wixobj files created by Candle. During its processing, it will look for -loc and -cultures flags given to it on the command line. You can specify more than one -loc flag, each pointing to a .wxl file. The -cultures flag tells WiX which .wxl file—or files—to use. Any that have a matching Cultures attribute in their WixLocalization element will be used. Here's an example:

Light.exe -loc en-us.wxl -loc en-us2.wxl -loc de-de.wxl
 -cultures:en-us "*.wixobj" -out myInstaller.msi

Here, we've specified that we want to build our MSI using the en-us culture. Assuming that en-us.wxl and en-us2.wxl both have that culture, both will be used. The de-de.wxl file will be ignored. You can specify more than one culture by separating each with a semi colon. This will set the first culture as the primary one to use and those that follow it as the fallback in case a particular string isn't defined in the first.

The next example builds...