.css lost when directory path altered for shared SSL (Drupal)

Testing a nonprofit's donation page (AuthorizeNet) in a Drupal 6.x site with civiContribute, I altered Drupal's .htaccess rewrite rules so that the page can use the Web host's SSL. The change was

RewriteBase /~primaryusername/nonprofittestsite (in the area of .htaccess near the end that deals with virtual document roots)

The page now loads (haven't tested it yet) at https://secure.bluehost.com/~primaryusername/nonprofittestsite/civicrm/contribute/transact?reset=n&id=n and I can see the certificate. However, this rewrite has caused the page to lose its path to the .css. It loads in an unstyled format.

I noticed this issue: http://issues.civicrm.org/jira/browse/CRM-4314 about a recent change to drupal/civicrm.module that makes the module more consistent with Drupal's way of aggregating files like .css.

I'm wondering if there is a hack I can apply to this area to help the /transact page find its way to the .css again ...? Or maybe someone has found another way to solve this problem in a virtual server environment using shared SSL?

(By the way, I see the source code of /transact is also referring to many .js files ... and I'm wondering if testing will show they, too, are now lost.)