I just tried out that module, and it worked okay once I fixed the .htaccess file that it generated in the secure folder. It's RewriteBase line was missing the base URL. Changing it to:
RewriteBase /
made it work.
There are a few things that I wish that it could do. The first being group access. Right now you have to add individual users to the list. In a lot of cases, it would be easier to define a user group, and then just select the group for folder access.
The other thing that would be great, is if this were expanded to work with the eCommerce module (which appears to be neglected of late), so that people selling digital products can easily create an online shop with downloads automatically activated once paid.
Hans