ACE latent growth modeling

Hello.

I am trying to assess stability and change of a phenotype with longitudinal twin data with latent growth modeling. Besides from a more advanced script (dual score) in the Boulder workshops I was not able to find an OpenMx script for this. Now I have three questions:
1) Does such a script exist somewhere for OpenMx?
2) Is it possible to achieve this with umxcp? Assuming a linear model, I would choose two factors and then fix the factor loadings accordingly?
3) If I included only two waves, would a bivariate genetic model achieve the same result (umxace)?

Thank you very much!