I reproduced this the first time I tried it, but have not been able to make it happen again since.
Are you able to make it happen easily, or does it only happen once/sometimes for you as well?
If it only happened once for you as well, let me know and I'll look in the direction of configuration data that might cause a problem only once (e.g. after updating from one version to another).
OTOH, if you're able to make it happen again easily:
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Process Snapshots while the window is frozen may help us locate the problem.
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Details of what the preset is may also be important. Details more likely to affect things are things like if the rename uses metadata, or is recursive over folder content, but other things may be relevant. A screenshot of the frozen window would let me try recreating the same settings.
As far as I can tell, I'm doing the same things I did when I got it to happen the first time, but maybe there are some details that make it more likely to happen and which I am not doing.