You need to manually install dependencies to make it running:
apt-get install libqt4-webkit
In order to use evopedia, you have to download a dump from
http://dumpathome.evopedia.info/dumps/finished/
(you can try with the "small" dump if the download is too long) Copy the directory on
your SD card, launch evopedia (its icon should appear with other applications),
click on the configure icon, and select the directory of you dump : it will
create a .evopediarc file for you. Then you will be able to search for an article.