context.PropertyDescriptor.SetValue(context.Instance, "MyValue")

Which uses the property descriptor to set the actual value on the design-time instance, which is then detected and serialized into the .designer.* file.

I have a property of type string that I created a custom ui type editor for. This part is working great the editor pops up and the text is reflected back on the property sheet for that property. However the changes to the property value are not serialized back to the class unless I manually type something on the property sheet. 

Even though the text I type in custom editor is being reflected back to the property sheet property value some event or something is not firing to know that the value of that property has changed. 

Any ideas?

Paul