Re: changing the encoding to utf-8
there is no Bulgarian language pack for this version yet
Get the latest Bulgarian language pack and convert all the files to utf-8 encoding (there are free bulk-encoders available).
Compare the file structure and CONTENTS to the english file structure and contents (use Beyond Compare).
Delete any files and constants/defines that do not exist in the english version.
Add the new files and constants/defines that are the english version. You don't have to translate them if you don't want (ie for admin files), just make sure they exist.
When all is working ok, upload your files as the new Bulgarian language pack.
"Totally Zenned" my a*se!