It's well known C4D and AE don't play nice, especially when they're both trying to render. But the "Cache Frames When Idle" is such a nice feature I hate to turn it off when I know c4d is going to be running and then forgetting to turn it back on after I'm done with C4D is a bummer.
It would be very handy and a nice timesave if we could tell "Cache Frames When Idle" to not do any Cache'ing when Cinema4D.exe or the program of our choice/s is/are running.