Hi Tinus,
Thank you for pointing this out.
Generally speaking, this is by design - a Service Pack release cannot coexist with a major release. This is why we throw a message that the previous version needs to be uninstalled, so that you are aware of what is happening.
We will try to automate the process to be more friendly.
Regards,
Jordan
the Telerik team
Check out
Telerik Trainer, the state of the art learning tool for Telerik products.