I am having the same issue. The message that appears is that I need to download the legacy Java SE 6 to run CellProfiler. I was using JDK 8 and also tried with Java SE 8, but neither worked. When I reinstalled Java SE 6, CellProfiler started again.
Any updates on whether CellProfiler will be compatible with Java 8? Or is this a Mac OS X problem? I know that the new OS is having some issues with Java, but not sure what the solution would be. Thanks for your help!