Issue with Adobe After Effects 18.4.1 crashing

We have been made aware of an issue when using Adobe After Effects 18.4.1 but it is only affecting our new ARM64 iMacs, the older Intel iMacs are fine.

The issue is when attempting to show our students how to use the Rotobrush tool in Adobe After Effects.

The second the students chose the Rotobrush tool and tried to click on the screen, all of the new ARM64 IMacs shutdown After Effects.

Ironically, the older Imacs, although slow, can operate the tool as it should be used.

The students tried rebooting the machines and reopening the software but the same issue occurred.

All iMacs, both ARM64 and Intel, are running Big Sur 11.6.3 and Adobe CC 2021. After Effects is version 18.4.1.

Can anyone offer any advice?