Isn’t Eclipse really hard to use?
No.
Why won’t my generated EMF Model Editor let me add children!?
If you have a model where one element should have children and the generated editor won’t let you add children, make sure that the “Containment” box is checked in the properties view for the association (the arrow) between the two elements. 
Here’s a link to a good, working model from Lar Vogel’s tutorial on EMF. I missed his containment remark in his text, but I found it in his ECore model:
How do I set the base package name of my EMF model?
One of the things I hate about EMF is that it has options for everything, but hides them in crazy places. I should be able to set the package name just by changing the package name! The solution is simple enough, but just took me a bit to figure out. Open your genmodel, select your package, open the “All” section in its properties and set the package name to what you want.
Jay's Whiteboard 