Having problems playing your Dreamoc movies ? And are you using Mac? 
It appears there can be a playback issue when copying movies from Mac to an SD/CF card. With the introduction of OSX 10.5, Mac changed the behavior of their hidden file structure. This is causing some compatibility problems across platforms in general. More information can be found here: http://en.wikipedia.org/wiki/.DS_Store

This tutorial shows you how to delete the hidden files and make your movie work when copied from Mac. There is no such issue when copying movies from PC.