You could always edit your site using your File Manager in cPanel and editing the code itself. If not, it may be best just to wait for RVSiteBuilder to return.
RVSiteBuilder uses its own proprietary format which is stored using Zend compression - the server understandsZend compression
If you do NOT have access to RVSiteBuilder the site's content (source code) will not be accessible by any other code editors (programs)
My advice is to avoid the convenience of site builders that use their own proprietary format, since your site's source code is then locked to their editor
Use a "site builder" that will let you create/update your site - then it compiles (makes) standard source files that you can edit with any code editor