So I am having an issue with the timeline, when I click a spot on it, the curser does not move at all, nothing even reloads or changes. I am on a Mac with Minecraft Forge 1.8 and I have installed FFmpeg
Please post the contents of the fml-client-latest.log file inside the logs folder inside your .minecraft folder to some pastebin site and link to the post here.
Note that this log will only contain information on the last time you started Minecraft, not any previous runs.
That log doesn't appear to match either. It has you joining a server, then a SP world, then exiting. Nowhere are you in a replay where you'd be able to click on the top timeline.