FileMgr::StartLogFiles: Operating system error 2 (The system cannot find the file specified.) occurred while creating or opening file 'd:\dbs\sh\sprel\0510_114453\cmd\31\obj\x64retail\sql\mkmastr\databases\ mkmastr.proj\modellog.ldf'. Diagnose and correct the operating system error, and retry the operation.
I don't what I did or how but it seems a glitch in the CTP version. The only thing I can think of is that I changed the data and log folder to the D Drive. I selected all the options in the installation process.
I solved it by creating the required path and copying the Master, Model, tempdb and msdb databases and copy to this location d:\dbs\sh\sprel\0510_114453\cmd\31\obj\x64retail\sql\mkmastr\databases\mkmastr.proj\
I had some problems with security of the folders and files :
FCB::Open failed: Could not open file d:\dbs\sh\sprel\0510_114453\cmd\31\obj\x64retail\sql\mkmastr\databases\ mkmastr.proj\model.mdf for file number 1. OS error: 5(Access is denied.).
But this is easily solved by adding the MSSQLSERVER account to the folders security and propagate this to this folders beneath it.
Next problem was that the administrator login/user was not present in SQL Server. I managed to solve that by executing the following steps: Stopping/Starting the SQL Server process (net stop mssqlserver) and run it in single user mode (net start mssqlserver /m), add the administrator account and give it sysadmin rights and then stop and start the SQL Server with normal settings(net start mssqlserver).