  We consider the critical behavior of the random q-state Potts model in the
large-q limit with different types of disorder leading to either the
nonfrustrated random ferromagnet regime or the frustrated spin glass regime.
The model is studied on the diamond hierarchical lattice for which the
Migdal-Kadanoff real-space renormalization is exact. It is shown to have a
ferromagnetic and a paramagnetic phase and the phase transition is controlled
by four different fixed points. The state of the system is characterized by the
distribution of the interface free energy P(I) which is shown to satisfy
different integral equations at the fixed points. By numerical integration we
have obtained the corresponding stable laws of nonlinear combination of random
numbers and obtained numerically exact values for the critical exponents.
