Here is one Silverlight tip from Mike Snow about how to dynamically load a control from a DLL. This is a nice Silverlight tutorial that deserves your attention.
Mike:
“If you have a large game or application it might be wise to break it up into smaller components that can be downloaded on demand. This way your customers are not stuck waiting for a large download to complete when first connecting to your application. In this tip I will show you how to load a Silverlight control from a DLL, create an instance of the control and add it to your Silverlight application.”