New translations have been finished in record time after a web interface for this task was made available. The german language pack was finished within less than 24 hours, followed closely by the russian and czech translations. More language packs  will be finished soon. They are automatically available in Trillian Astra. A manual installation is no longer necessary. Updated language packs are distributed via the Trillian auto update feature. 

The following screenhots show how the language is chosen in the preferences and the corresponding language pack is automatically downloaded and installed:

You may also change the language directly after the installation: