Unable To Reference Wizard Assembly in VSIX Deployed Template

When deploy the wizard based project template by VSIX Extension, it is better to use Short-Named assembly in .vstemplate. This can avoid the GAC deployment.

In your case, it should be:

<WizardExtension>
 <Assembly>My.Assembly</Assembly>
 <FullClassName>My.Assembly.Wizard</FullClassName>
</WizardExtension>