Experience with gypsum-cement plaster for interiors

Do you have positive or negative experiences with gypsum cement plaster for interior spaces (living areas and damp rooms)? Please no wild guesses or speculations.

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Please no wild guesses and speculations.

Strong performance for the first time!

Wasn't meant to be mean
Just find all the "I don't really know, but ..." answers terrible.

Well, then off to the independent building physicist... of course, he doesn't do it for free

No offense intended
I just find all the "I don't really know, but ..." answers terrible.

And users who could report something find conditions for an answer terrible.
Just let it be done in a forum and pick out the helpful information.
That was advice that should basically apply - I know our forum members and forum here: something like that does not go over well.

Carry on now!

The addition of calcium sulfate (gypsum) as a setting regulator causes a delay in setting from ten minutes to around two hours. Fine ettringite crystals form in the process, which delay the chemical water uptake/water binding. Sulfate-free cement, on the other hand, sets immediately. However, the optimal mixing ratio between gypsum/cement should be determined at the factory. Using your own formulations is not recommended, as this usually leads to setting problems and a more or less unusable result.