upgrade to last version

I want to update up to last version.
At me the version ver.2.0 RC4b. I download the distribution kit and a file of converting.
Has executed converting. The ambassador has removed all files on a forum, except for setup_options.php, has added in this file last lines: $startIndex, $manualIndex. Has added files of Russian lang.
After all it has tried to start a forum, but have appeared толко names of sections. Messages were not. What I not so do? Language Russian.

Our software comes free but with no warranty. It could take us a long time to investigate what's wrong case, so we are providing only paid support on such kind of topics.

I could say additionally this could happen because you have not added new database fields for posts, topics, forums table etc. What exactly fields? Pay us if you can't find yourself...