Help!!!

I’m using Encore CS4 to burn blu-ray discs and am having a chapter issue. I have a single timeline project with 4 video assets on it. When the video goes from one the first asset to the second it plays black for an undetermined amount of time. It does the same thing between the second asset and the third. If I skip forward I get to the next chapter but it will not play through. Does anyone know how to fix this issue?

I tried to solve the problem by putting my assets on separate timelines but the blu-ray navigation in encore will not allow the viewer to skip back to previous timelines limiting navigation. Is there an action to get back to previous timelines? My title button does take the viewer back to the very beginning of my timeline.