  The class XNLP consists of (parameterized) problems that can be solved
nondeterministically in $f(k)n^{O(1)}$ time and $f(k)\log n$ space, where $n$
is the size of the input instance and $k$ the parameter. The class XALP
consists of problems that can be solved in the above time and space with access
to an additional stack. These two classes are a "natural home" for many
standard graph problems and their generalizations.
  In this paper, we show the hardness of several problems on planar graphs,
parameterized by outerplanarity, treewidth and pathwidth, thus strengthening
several existing results. In particular, we show the XNLP-hardness of the
following problems parameterized by outerplanarity: All-or-Nothing Flow, Target
Outdegree Orientation, Capacitated (Red-Blue) Dominating Set, Target Set
Selections etc. We also show the XNLP-completeness of Scattered Set
parameterized by pathwidth and XALP-completeness parameterized by treewidth and
outerplanarity.
