I cannot help you fully but...
When a case is run, Code_Aster generates some temporary files (vola.1, etc) that contain the information of the simulation. Normally, these files are saved if the case fails and the data needs to be recovered. This is usually done by creating a new case and using PROSUITE() and analyzing the Code_Aster files using CA commands... I have never done this myself, so I cannot guide you much further than that to be honest... I normally just decrease the simulation time just right before it crashes and I analyze what is going on there. If it all seems alright and it is a slow simulation, I just use a reload the results in a new case and keep on with the simulation results more or less...
Best regards,
Fer