You have not provided any system info or other details like what image sequence and so on, so we can't really know. Either way, ask in the LR forum and provide all that info.
If you have creative cloud, there is a far better way to make a time-lapse using Photoshop. The Lightroom way works but is a very slow kludge that creates files that you have to recompress to make them work. I would only use this if you don't have Photoshop or quicktime Pro. Here is the first link that shows up when I google "creating timelapse with photoshop": http://photofocus.com/2014/02/06/assembling-a-time-lapse-video-in-adobe-photoshop/
So to be sure you know what I mean, Take your Lightroom edits. Export them to a folder of sequentially numbered sRGB jpegs of reasonable size (say 3840 pixels on the long side so you can make a 4K video) and set up the project as in the video linked to before. You can now do a simple direct time-lapse or throw in a pan and zoom in the Photoshop timeline, add a title caption, fades, etc. Here is an example of a time-lapse I created this way: Jao's photo blog: The Polar Vortex - Star Wings