I am having trouble with the new stata 16 cmxtmixlogit command.

I am trying to estimate a choice model for repeated-choice 'unlabeled' discrete choice data, where one of my alternatives is essentially a status quo alternative and I would like to include an alternative specific constant (for one out of my three alternatives) as a normally distributed random parameter. I have other random parameters in the model, including correlations and constraints.

It seems that cm- commands are more applicable for 'labeled' choice data but I cannot do my specification using mixlogit.