start terminal, and paste the following:
defaults write EigenD.app NSAppSleepDisabled -bool YES
Note: I know this IS necessary if EigenD is built on Mavericks (e.g. from open source build)
I cannot tell if its necessary for the released version (2.0.74 and prior). ... I suspect that it IS NOT necessary... as Ive not noticed an issue, but if you have issues with performance might be worth trying