Is the crash of resource catalog you refer to mean mouse click on any button just get ignored, and the resource catalog is gone as if nothing has happened?
To create self association, instead of using the resource catalog, you can select the Association button from the toolbar. When create a normal association, you would then drag from the source class to the target class, but since you now want a self association, you just single click on the class without dragging the mouse at all.
For the “second creation will change name” behavior, it is because currently multiple self associations will default be layout the same way, so the second (and up) self associations created will covered the previous. So actually the self association is there, just drag the connector points manually to reveal it. We are sorry if it confused you, and we will enhance this feature.