I have only added 3.8G of video files to my DVD compilation, why does PowerDirector tell me there is no more space? Does PowerDirector add up the file size incorrectly?

PowerDirector estimates the total size used, and compares that to the maximum capacity allowed by the disc format. Please remember that the slideshows, background music, and menus also require disc space.

In addition, Disc Wizard encodes all audio into LPCM format, which is larger than the MPEG audio format used by MPEG clips.