I am also experiencing the same king of issue.
I am working on screen capture course, with about 350 slides, and I see the problem when:
1- adding new content
2- copy and paste audio files between slides
3- copy/duplicate a slide
4- action fine tuning on videos (the operation starts, then it fails to save the new edited video into the slide and program freeze..causing me to force Storyline's closure
I was working with iMac with i5 Win7 64GB 4GB RAM, running windows on Virtualbox
I arrived at the point where I cannot insert a new slide, cus ev'thine I saw an error message.
I tried adding 4GB RAM more.
The problem has been solved for parts 1 and 2. Errors 3 and 4 persists.
I will try Jonathan's suggestion..
I love using Storyline, but that said I'm not so confident with hardware and I cannot give an answer, but I am wondering why a new and important software such as Storyline is, has been built for a limited use with new OS, causing problems to users.