Hi @InfiniteWhale,
Thank you for reporting this issue. I've moved your message to its own thread so we can focus on what you're encountering.
A log file would be the best place to start to see what is causing the hang you are seeing. Please choose Help > Enable Logging, then restart After Effects as prompted, then perform the actions that are causing the hang. Then go to /Users/<yourUserName>/Library/Preferences/Adobe/After Effects/25.0/logs and share the contents of the "After Effects Log.txt
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