  This paper develops techniques which are used to answer a number of questions
in the theory of equivalence relations generated by continuous actions of
abelian groups. The methods center around the construction of certain
specialized hyper-aperiodic elements, which produce compact subflows with
useful properties. For example, we show that there is no continuous
$3$-coloring of the Cayley graph on $F(2^{\mathbb{Z}^2})$, the free part of the
shift action of $\mathbb{Z}^2$ on $2^{\mathbb{Z}^2}$. With earlier work of the
authors this computes the continuous chromatic number of $F(2^{\mathbb{Z}^2})$
to be exactly $4$. Combined with marker arguments for the positive directions,
our methods allow us to analyze continuous homomorphisms into graphs, and more
generally equivariant maps into subshifts of finite type. We present a general
construction of a finite set of "tiles" for $2^{\mathbb{Z}^n}$ (there are $12$
for $n=2$) such that questions about the existence of continuous homomorphisms
into various structures reduce to finitary combinatorial questions about the
tiles. This tile analysis is used to deduce a number of results about
$F(2^{\mathbb{Z}^n})$.
