Hi
I am having this issue on my Mac since reinstalling LRT ? Any idea why it wont render?

Steve

[2015-10-13 10:12:26] DEBUG: Launching mpeg converter: ffmpeg
[2015-10-13 10:12:26] DEBUG: Rendering in 1920x1280
[2015-10-13 10:12:26] ERROR: Could not launch encoder
java.io.IOException: Cannot run program "ffmpeg": error=2, No such file or directory
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1041)
at lrtimelapse.v.a(Unknown Source)
at lrtimelapse.v.doInBackground(Unknown Source)
at javax.swing.SwingWorker$1.call(SwingWorker.java:296)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at javax.swing.SwingWorker.run(SwingWorker.java:335)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:744)
Caused by: java.io.IOException: error=2, No such file or directory
at java.lang.UNIXProcess.forkAndExec(Native Method)
at java.lang.UNIXProcess.<init>(UNIXProcess.java:135)
at java.lang.ProcessImpl.start(ProcessImpl.java:130)
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1022)
... 8 more

I assume, you are using LRTimelapse 3 on the new Mac OS 10.11. This is not supported, since Apple changed a lot of things.
LRTimelapse 4 supports the new MacOS. Please upgrade.