I remember the first questions on our forums and support tickets about minimizing the size of Telerik UI for Silverlight assemblies. We took this feedback very seriously, like we always do when we hear from you how we can improve our products, and in the beginning of 2010 we introduced the Assembly Minifier. Its sole purpose was to reduce the size of Xap files and SL assemblies.
The Minifier was on its duty for more than four years now but it appears that it cannot keep pace with ever-changing development needs. It’s time to pass the baton to other great tools and techniques and go to a deserved rest. Yes, it is official–we discontinue the support for the Telerik Assembly Minifier. We will not introduce any new features or fixes, but it will still be operational on its current location.
There is no need to worry. Instead, have a look at this blog post which presents different approaches for reducing the size of your XAP. You can combine them with the NoXAML version of our assemblies, so that you can use the controls' logic and the xaml styles only for the Telerik SL controls you need.