I recommend to realize that during beta testing the support is 'where possible', and I strongly recommend to take preventive measures to get the best results:
Back up your data.
Upload the .zip as a whole to the server, unpack in a different directory.
Close the board (even though you don't have to) putting it behind .htaccess (so ppl can't load it)
cp -rfv upload/* ../public_html/ (in other words, copy the files, overwriting the existing files)
And run the install/ from the browser.
- Make sure debug mode is disabled.
When successful, check the board, remove .htaccess.
Then archive the backup of beta1 offsite, and delete the temporary and now obsolete beta2/ dir.