Hi Sebastian,
If you want to install SQL Server 2008 R2 automatically, you could try to use command prompt.
When installing through the command prompt, SQL Server supports full quiet mode by using the /Q parameter, or Quiet Simple mode by using the /QS parameter. The /QS switch only shows progress, does not accept any input, and displays no error messages if encountered. The /QS parameter is only supported when /Action=install is specified.
Install SQL Server 2008 R2 Using SysPrep: http://msdn.microsoft.com/en-us/library/ee210664(v=sql.105).aspx.
How to install SQL Server 2008 R2 from the Command Prompt: http://msdn.microsoft.com/en-us/library/ms144259(v=sql.105).aspx.
Thanks,
Maggie
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