Thank you for contacting us. Yes, you can create a separate project to house your MVC controls.
Take a look at the following forum post (look for the 2nd post by Brett Whittington, little more than halfway down). He goes into how he has created virtual directories for all of his shared code:
As for adding custom widgets to your toolbox, please refer to the following documentation:
Let us know if you have any additional questions or need any clarifications.
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