In this paper, we combine methods in \cite{DB} and \cite{KPT} to compute
universal minimal flows of groups of automorphisms of uncountable
$\omega$-homogeneous graphs, $K_n$-free graphs, hypergraphs, partially ordered
sets, and their extensions with an $\omega$-homogeneous ordering. We present an
easy construction of such structures, expanding the jungle of extremely
amenable groups.
We show that Lelek's problem on the chainability of continua with span zero
is not a metric problem: from a non-metric counterexample one can construct a
metric one.