When you install the OBA Composition Toolkit, maybe you have to face the provisioning problem described a few days ago. One more detail about this issue: during OBACT installation these tags will be inserted into the web.config file of SharePoint Server Central Administration's web application:
<add key="OBAAdministration" value="http://spsdemo:21212/CompositionServer/Administration.asmx" />
<add key="OBACompositionInstallerPath" value="C:\Program Files\CompOBARefToolkit\" />
If the last one is missing, the proper database field will be empty, so the provisioning is failed.