Language Manager is available through "Options->Languages..." menu.
The purpose of Language Manager is to allow translate WIDI's interface to any language, switch between languages and save or restore translation form text file. The process of translating WIDI to other languages is described in How to Translate WIDI section.
Select Active Language list contains the list of available localizations. You can select a language from the list, and it will be applied restart. The list of languages contains several pre-installed languages and translation that were added manually.
Delete allows to delete chosen translation form list. If you accidentally deleted an appropriate pre-installed translation, add it from the installation WIDI language directory (most likely it is something like "C:\Program Files\WIDI 4.0 \Localizations").
Add Language File
This section allows to add new localization to WIDI or update old localization with new translated strings.
Add button invokes Open dialog to select new localization file to add. The selected file will be copied to WIDI settings directory and will appear in Select Active Language list.
Merge with Current invokes Open dialog where you can select a file with new translated strings which will be added to the selected localization.
Get Existing Language File
This section allows to import translation files to create new localization or to make changes to existing localization.
Selected language indicates base language for the localization, so if you want to translate WIDI from Spanish to French, select "Spanish" here.
Get All Strings saves localization file chosen in the list above. After translating the file into another language, use Add button to import the translation into WIDI.
Get New Strings allows you to get strings that does not exists in an older localization file. The button invokes Open dialog to select older localization file, compares it to current language file and exports all strings that are do not exist in the older file. After translating these new strings use Merge with Current to merge the file with appropriate old localization.
Note: You may translate WIDI into new language from any language that WIDI is localized into, not necessary English.
See How to translate WIDI section for comprehensive explanation of WIDI localization process.