At long last the issues with Aperture have settled down and the app is behaving normally. I read periodically on forums that users are still unsure of the viability of installing 3.1. The only caution I would mention is just be aware that once your libraries are updated you cannot revert to a previos version of Aperture, it’s a one way street, and if you get stuck, heaven help you. Having said that the 3.1.1 update has it’s merits and is worth the effort. Although in the interim when Aperture was down I discovered that Lightroom is no lightweight and is a serious contender. Apple beware, Adobe are doing their homework.
The update solution and now obviously the crash solution are posted here for reference.