I'm a long time Mac developer, started on OS 7.5.1. I have this thing about the beach ball and a terrible to urge to educate people about it! Forgive me
The beach ball means an application has not responded to user events for a certain time, I forget what it is. 2 seconds I think. An application has an event queue that the operating system puts events ( i.e. mouse clicks or movement, key presses, redraw requests etc. etc.) into and normally an application will be pulling those events off the queue and dealing with them. If the OS decides the application hasn't done that recently enough it puts up the beach ball. When the application starts to respond to events again it takes it down.
Sometimes the beach ball will come up because an app is completely hung. That's not often the case in my experience. More commonly it's because it's busy doing something processor intensive and it's not processing events. It's in a loop working hard. That's what it sounds like you're seeing C4D doing.
A few years back Apple really started encouraging developers to do these sorts of intensive operations on a different thread to the user interface. This means that the user interface can stay responsive while the app is working away. It stops the beach ball from being shown. I think Apple also shortened the time before the beach ball was shown as an incentive for developers to make those changes. I do think that made quite a difference to how often you see it.
Lots of people think the beach ball means a crash but most of the time that isn't the case.
I thought the video was pretty funny. I liked the use of the system beep in the music

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