Thunderbird 2 Release Candidate 1 Bugs

I just tried TB2 RC1 and didn't find any Topic to post my bugs so I start a new one.
I extracted the "new" copy to my desktop and copied my "old" Data folder over.

1. I love the new look.
2. Apart from several extensions not being compatible, everything worked.
3. Only the new talkback extension and the birthday reminder extension worked.
4. I think, the "use this TB as a default client for:" check at startup should be disabled/removed.
5. Leaves these folders
   [Moderator note: Line wraps marked »]

   
   C:\Documents and Settings\username\Application Data\Thunderbird
   C:\Documents and Settings\username\Application Data\Talkback
   C:\Documents and Settings\username\Application Data\Talkback\MozillaOrg\
   C:\Documents and Settings\username\Application Data\Talkback\MozillaOrg\Thunderbird2\
   C:\Documents and Settings\username\Application Data\Talkback\MozillaOrg\Thunderbird2\
   » Win32
   C:\Documents and Settings\username\Application Data\Talkback\MozillaOrg\Thunderbird2\
   » Win32\2007032620
   

   and these files:
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   C:\Documents and Settings\username\Application Data\Talkback\MozillaOrg\Thunderbird2\
   » Win32\2007032620\manifest.ini
   C:\Documents and Settings\username\Application Data\Talkback\MozillaOrg\Thunderbird2\
   » Win32\2007032620permdata.box

6. Leaves stuff in my Registry:
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   ----------------------------------
   Schlüssel hinzugefügt:3
   ----------------------------------
   HKLM\SOFTWARE\FullCircle
   HKLM\SOFTWARE\FullCircle\TalkBack
   HKLM\SOFTWARE\FullCircle\TalkBack\MozillaOrgThunderbird2Win322007032620
   
   ----------------------------------
   Werte hinzugefügt:1
   ----------------------------------
   HKLM\SOFTWARE\FullCircle\TalkBack\MozillaOrgThunderbird2Win322007032620\Thunderbird.exe: 
   » "D:\ThunderbirdPortable\App\Thunderbird\Thunderbird.exe"
   

Thats all.