This builds easily on both arches, using essentially the same cygport
file as Yaakov used for icu-51.2-1 on x86_64. I tested it by rebuilding
the TeX Live binaries against libicu54.
D=http://sanibeltranquility.com/cygwin/x86/release/icu
wget -x -nH --cut-dirs=1 \
${D}/icu-54.1-1-src.tar.xz \
${D}/setup.hint \
${D}/icu-debuginfo/icu-debuginfo-54.1-1.tar.xz \
${D}/icu-debuginfo/setup.hint \
${D}/icu-doc/icu-doc-54.1-1.tar.xz \
${D}/icu-doc/setup.hint \
${D}/libicu54/libicu54-54.1-1.tar.xz \
${D}/libicu54/setup.hint \
${D}/libicu-devel/libicu-devel-54.1-1.tar.xz \
${D}/libicu-devel/setup.hint
D=http://sanibeltranquility.com/cygwin/x86_64/release/icu
wget -x -nH --cut-dirs=1 \
${D}/icu-54.1-1-src.tar.xz \
${D}/setup.hint \
${D}/icu-debuginfo/icu-debuginfo-54.1-1.tar.xz \
${D}/icu-debuginfo/setup.hint \
${D}/icu-doc/icu-doc-54.1-1.tar.xz \
${D}/icu-doc/setup.hint \
${D}/libicu54/libicu54-54.1-1.tar.xz \
${D}/libicu54/setup.hint \
${D}/libicu-devel/libicu-devel-54.1-1.tar.xz \
${D}/libicu-devel/setup.hint
Ken