regularized multiphase lattice boltzmann

Hi to everyone

I’m new to this forum. First of all I would like to say that this is one of the best and useful site about LBM.
I have a problem.
I would like to implement a regularized (Latt 2006) version of the multiphase shan chen lattice Boltzmann method but I met some problems.
Indeed when I ran a simple test case (droplet formation) I get some strange results that is:
when i use a value of tau (relaxation time) different from one the minimum(vapour) and maximum(liquid) densities are different from those predicted.
I would like to know if one of you have had the same problem and if you have aany suggestions to give me.
P.S.
I used the regularized LBM algorithm to simulate single component single phase flow and it works well.

Thank you in advance

Andrea