There really isn’t any more documentation. You do need to write your own attemptRecovery handler since the steps to recover will be specific to your testing environment. You need to make sure that if your attemptRecovery script actually does anything that might fix things on the SUT, that it returns “TRUE”. If you don’t set the return value, then the Omega13 script assumes that nothing was found that could be repaired and it will just let the main script fail.
The sorts of things that Omega13 were meant to deal with are events like the Windows Update window appearing or other random events that are not driven directly from the events in the application being tested. As such, it’s often an iterative process to create an attemptRecovery script that covers those scenarios. It’s worth noting that when a script fails, eggPlant captures a full resolution screenshot, and that you can capture images from that screenshot to use in your scripts. So if you get a failure because an unexpected and previously uncaptured dialog appeared on the screen, you can extract an image of that dialog from the error screenshot (using the Preview or Paint app, for example) and add a check for it into the AttemptRecovery script. Note that if you do this, you can save the captured image into the Images directory, but you will then need to select the image in the eggPlant Suite window and open the Info drawer and edit the search type (which will be Precise by default and should probably be Tolerant or Text as required).