This is a major nuisance I'm experiencing. I'm using the Melodyne ARA integration in Sonar X3 Producer by using Melodyne as a Region Effect (as it says you're supposed to do in the documentation) ...  I spent a few hours last night adjusting some vocal takes with the Melodyne integration -- saved the project, exited... fired it back up today and Melodyne is still in the regional FX bins, but all of my edits are GONE. What happened??

Good question. I've used it numerous times in X3 to tighten up timing on tracks and I'm pretty sure my changes stuck after exiting. I might even have a few projects kicking around where I haven't rendered the changes yet. I'll have a look later on and see if the edits are still there.

Did you Bounce to Clip or Track before closing??

OK, just checked a project where I'd used Melodyne to make some timing changes, hadn't rendered the region fx, but saved and closed the project. All changes were still in tact when I re-opened the project. Not sure what happened in your instance. HTH in some way.