Composer bundled executor freezes my computer

Hi,
every time I run my tools or workflows using the bundled executor available in Rabix Composer, my machine starts to be really slow and then freezes. It is an Ubuntu 18.04 VM (on Mac OS) with 8 GB RAM. I get this odd behaviour only with Rabix-composer.
What could I do to solve this problem?
Thank you for any help you could provide.