what I understud from your posts is that you installed cssu testing first then you tryied to install cssu stable over the testing version so if I am right that is not polssible you should read the instructions first on how to install, there is mentioned that onces you have installed the cssu testing there is no way back to the stable version or the original maemo PR so looks to me that you will have to reflash your device, hope you have a backup, unless someone can sugest other solution.