Anyone having racing issues on their Mac?

Hello, I am a new user of iStopMotion and I noticed my MacBook ventilation running on high and the hard drive heating up when this was running. I mean more than usual. Over 10GB of free space on the drive and not all of the memory was being used (8GB RAM in system, nothing else running). We left the software running for lunch and when we cam back the system was quite hot. So, is there some special sort of hard drive access going on or has anyone heard of this? Otherwise the program worked fine.