If it's saying that you have an "incompatible renderer", then you very likely still have a composition set to use the ray-traced 3D renderer. Since we can't see what your composition consists of, I can only guess that you have a nested composition still set to the ray-traced 3D renderer.
BTW, don't spend a lot of time trying to force Render Multiple Frames Simultaneously to work. This feature is only sometimes beneficial.
Thanks Todd, i checked all my nested pre-coms and indeed one of it was set to ray trace.
May i also ask if performance is better if more processing core is being used?
For example, if i set my RAM allocation to 1gb per core, i can get 10 cores to be used, where if i set it to 2~3 gb of ram per core i get 4~6 cores to be used.
Which of my two examples is better?
Typically im working on 720 & 1080p comps only. Thanks in advance.
> Which of my two examples is better?
The easiest way for you to know for sure is to try a test with each.
See this page for information about memory and improving performance in After Effects: http://adobe.ly/dC0MdR
See this page for resources about making After Effects work faster: http://adobe.ly/eV2zE7