I now am running 24.0.0 on a macbook pro. I get no preview feedback now when using liquify, and without preview the tool doesn't work for me. I thought the tool was broken completely but I noticed my edit history showed I was doing things, and I could see the effects when I closed the tool. But when pushing, changing any slider, etc. I don't see anything changing in the liquify window. I toggled the preview checkbox a few times with no difference. I use the tool now and then and I'm not doing things differently far as I know.
I have another system running 23.5.2 which I just brought up and it works the usual way.
Since your question is about Photoshop, I have moved this from the Photoshop Fix forum where you posted. PS Fix is no longer supported, so your post sat there for a while. Hopefully you have updated to 24.1? Is it still an issue? Can you post a screenshot with your settings?