I think one common mistake beginners or even pros make, is in the calculation of deterministic steady state, sometimes due to nothing other than typos.

There should be a functionality that, tells you, if the convergence at deterministic steady state is NOT achieved in step 0, which equation is causing the problem that is preventing convergence at deterministic steady state to be achieved immediately given the guess of steady states.

I.e., there should be a printout like

eq 1, resid0

eq 2, resid0

eq 3, resid=0.0333

etc, so we can easily debug the mod file.