The team of designers, animators and programmers worked together to make it a beautiful experience, while maintaining some form of accessibility and SEO.
To do that, the whole Flash app gracefully degraded to a separate pure-HTML version, essentially duplicating the project.
I helped to get data from MySQL through an API built in PHP, which was read through ActionScript in Flash.
It was a convoluted system, but that was required to get data into Flash. In many ways it’s akin to what frontend apps are doing now (but we had a 100% custom interface).