Skew LRS of maximal period over Galois rings

Let $p$ be a prime number, $R=\mathrm{GR}(q^d,p^d)$ be a Galois ring with $q^d=p^{rd}$ elements and characteristic $p^d$. Denote by $S=\mathrm{GR}(q^{nd},p^d)$ a Galois extension of the ring $R$ of dimension $n$ and by $\breve S$ the ring of all linear transformations of the module $_RS$. A sequence $v$ over the ring $S$ satisfying the recursion $\forall i\in\mathbb N_0\colon v(i+m)=\psi_{m-1}(v(i+m-1))+\dots+\psi_0(v(i))$, $\psi_0,\dots,\psi_{m-1}\in\breve S$, is called a skew LRS over $S$ with a characteristic polynomial $\Psi(x)=x^m-\sum_{t=0}^{m-1}\psi_tx^t\in\breve S[x]$. We investigate the problem of construction the polynomials $\Psi$ generating LRS $v$ with the maximal possible period $\tau=(q^{mn}-1)p^{d-1}$.