FAIL: Upgrade Omega 3.0-RC2 to Omega 3.0

Dear Readers,

I encountered much the same behavior as described by modulist ("Upgrades to 3.0-rc2 and 3.0-rc3 cause missing HTML, other bizarre behavior", http://drupal.org/node/1239944).

Luckily, it only happened on my trial server, not on a live website.

I'm running Drupal 7.7 and - aside from the issue I brought to attention at http://drupal.org/node/1233060 - there were no problems.

Maybe the fault lies with me:
I simply removed the old omega folder (7.x-3.0-rc2) and replaced it with the new one (7.x-3.0) using the path ".../sites/all".
After clearing all caches and running cron, my site was gone for good.

How can I find out what went wrong? Is there a Omega 3.0-Update documentation to be found on the web?

I would appreciate any hints.

(For the time being I revert to RC2 and continue developing.)

Thank you very much in advance,
GeorgHuber