Hi
We are currently in the process of migrating from WebSitePanel to HC and with WSP we used to use Helicon APE.
Helicon APE is an excellent replacement for IISPassword and more. It allows Linux people to keep their precious .htaccess or .htpasswd files and simply upload these to the IIS web server and they work.
If HC already has support for IISPassword then they are 99% there as the file format is the same I believe.
Yes you have to purchase a license for Helicon but I am sure HC could liaise and get some control panel discount that they could pass onto us.
Check it out here
We love it!
Regards
Mark Donne