  In this note we show that there are no real configurations of $d\geq 4$ lines
in the projective plane such that the associated Kummer covers of order
$3^{d-1}$ are ball-quotients and there are no configurations of $d\geq 4$ lines
such that the Kummer covers of order $4^{d-1}$ are ball-quotients. Moreover, we
show that there exists only one configuration of real lines such that the
associated Kummer cover of order $5^{d-1}$ is a ball-quotient. In the second
part we consider the so-called topological $(n_{k})$-configurations and we
show, using Shnurnikov's inequality, that for $n < 27$ there do not exist
$(n_{5})$-configurations and and for $n < 41$ there do not exist
$(n_{6})$-configurations.
