Discuss exercises in the manual / and examples in the documentation: great for new users!

Based on the [two-factor model](https://vipbg.vcu.edu/vipbg/OpenMx2/docs//OpenMx/latest/FactorAnalysis_Path.html#two-factor-model ) and [joint ordinal-continuous model](https://vipbg.vcu.edu/vipbg/OpenMx2/docs//OpenMx/latest/Ordinal_Path.html#joint-ordinal-continuous-data) examples in the documentation, I tried creating two single-factor models (one continuous and one ordinal), which I tried to combine in a new model. In the new model essentially just tried to add a covariance path between the latent variables.