Dictionaries are available for download from the following page: http://www.essentialpim.com/get-epim/dictionaries.
1. Download the dictionary file
2. If you are using Desktop version, unpack the file into: C:\Users\User_name\AppData\Roaming\EssentialPIM\Dict. If you are using Portable version, unpack the file into EssentialPIM installation directory.
3. Run EssentialPIM, the installed dictionary should be instantly available.