Creating widgets in a separate library seems to be a great idea, but there are some obvious things that we're having difficulty with:
We can't find documentation anywhere indicating what type of project you're supposed to create so we assumed a regular C# project.
We added a reference to our Sitefinity project's Telerik.Web.UI assembly as well as the Design and Skins assemblies as you can see in the attached References.png file. Then...
We register RadControls like this on the user control:
<%@ Register Assembly="Telerik.Web.UI" TagPrefix="telerik" Namespace="Telerik.Web.UI" %>
As you can see from the attached image "Ascx At Register.png" RadControls are still not recognized.
When I added the new widget to the project using Thunder, it correctly registered it in my Sitefinity project and the Wizard control does actually show up on a Sitefinity page when I drop the widget onto a page.
Resource Not Found
The next problem we're seeing is that the next button keeps rendering out on the browser with the text "#ResourceNotFOund#;RadWizard:Next" as can be see in the attached image "Wizard Resource Issue".
To this end we've tried
We're not sure what else to try but so far our efforts in the external widget assembly haven't gone too well!
It's a Sitefinity project. Are you saying it IS or IS NOT possible to create widgets in separate essemblies/projects? (And use the RadControls version that comes with Sitefinity inside that external assemby?)
Regular Asp.net controls like labels and validation controls work fine.
I can provide the example, but zipped it's 32Mb so where would you like me to put it?