I've had nebula for months and haven't been able to figure it out. Finally got it working with your help.
I un-installed Nebula3, and installed the latest version. Then I realized my Nebula3 was authorized, but the Nebula3 Reverb was not. So I requested that Nebula3 reverb license, and replaced the INIT.N2P and INIT.N2V files in my nebulatemprepository and now it's working (no longer displaying "init" for all programs).
Now nebulaman is previewing with effects as expected!