no, there were quite a handfull of short videos like tragedy mule in the long void between 2d and 3d versions, as new features were being developed and demonstrated. but pre-release videos would be long before that time, and much before Markavian put up the map archive and added video functionality.
Heck, I wasn't even here when 2D mode had the undead invasions. I'm going to go out on a limb and say that anyone who remembers that, they were probably a B12 fan before DF was even announced, which could easily be something like 10 years? I'm not really sure.