If you need support from Yola please contact us via support@yola.com or make use of our live chat service! We are working on a new approach to community-based support and during this transition period we are not adding any new threads to this forum. Many thanks to everyone who has participated over the years and we look forward to unveiling a new peer-to-peer support system soon!
Yola sitebuilder is a dedicated system which doesn't allow for other building systems. The sites must be built with the Yola sitebuilder to work.
Having said that you can use CSS and generated content HTML to add to your site. You can't use other third party templates for building a site with Yola.
So you can't upload a third party website building program for use with Yola. It is disappointing I know but the system is designed for easy use which can be fully supported by the CS people of Yola whereas third party software is just too big a frontier plus the potential security issues and platform design to enable this.