I haven't experienced the problems with macros and scripts that you seem to be, so I can't really comment too much on that. Especially when trying to work concurrently on a single design with other individuals. In my experience, there's just too much opportunity for uncertainty and error in a flow like that, so I tend to avoid it. Particularly when there are better tools available.
That said, if you can give an indication of the commands you're running in the macro and how/when they tend to fail on you, maybe I can reproduce a similar effect on some of my designs and offer strategies.
I'd definitely suggest reading the user docs available on design partitioning. You could also check out the online self-help pages and applications notes on the subjects, or talk with whoever is your Cadence support rep about it. They could feed you more information, I'm sure. It's designed to overcome a lot of the issues that you seem to be working around manually (like posting a "master" to the server at the end of the day, periodically reading in master constraint files, etc). The reports, ECO wizard, email notifications, etc. all provide me with a lot of value, particularly when it comes to peace of mind, over trying to manage it manually and fearing that I've forgotten something.