Mostly just a reminder to myself, silverlight XAP files are just ZIP files renamed, if you need to change a connection string or something in the config, just open it, change it and save it.

It seems there are some rendering performance issues with the Telerik drop down, but I was able to find a fix on one of the Telerik blogs. It is an older post and the namespace on the controls is not what is default now, but it still works. It is basically changing out the embedded control that is used for rendering from a RadComboBoxItem to a virtual stack panel. It took the performance I was seeing from unacceptable to instant.

You can read more here: http://blogs.telerik.com/valerihristov/posts/09-10-28/virtualized_telerik_combobox_for_silverlight.aspx