Hi,
If you are trying to render one job while working on another, you can use the command line renderer.
Just so long as you have the GUI version running before you start the command line version, there should be no problem with continuing to work on a project while you render in the background. Just don’t use the “reuse” flag.
My usual work flow is to work on a project and then when I have something I need to render, I reduce to project to just what I need to render, send it to the render queue, save the file, usually with the word “reduced” in the filename (so I know to throw it away after I’m done rendering), then run the command line renderer on it. I then reopen the original file and continue working on some other animation while the previous animation renders. Remember, don’t close the GUI version of AE while you start up the command line version or else the GUI version may refuse to start until the command line version finishes.
I have been doing this on a G5 OS-X 10.4.7 AE Ver. 7 and it has been working consitantly well for me.
Hope this helps,
Lars