You can just plug in your map to the transparency node and set value to 1. Not sure how you can save it so you can reuse it without overriding though. Usually, you will just click the + sign in the material room and save the whole thing or just one node, but when you load that mat again, it is going to override everything there. Check out ArtBees Missing Poser Manuals as it may help or wait until one of the gurus comes along.

Have a creative day!

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