To assign different ASP.Net version from your account which using WebSitePanel, you may refer to the
step as below,
1. Login to your WebsitePanel via http://cp.domain.com.
2. Select the Hosting Package such as RW1000 Windows Reseller Plan.
3. Select the Web Sites option at the Web & Applications category.
4. When you reach the Web Sites page, you may click on your domain (eg, domain.com).
5. Next, click on the Extensions tab then you may change the version by clicking the ASP.Net version.
6. Lastly, click Save Changes and Exit or Save Changes to update the ASP.Net version.