In short: do not install both overlays on the same machine at the same time. Use one of them. Period.
If you happen to encounter an error with either one, feel free to join #gentoo-e on freenode,
See https://bugs.archlinux.org/task/29643?o ... us%5B0%5D=To solve this issue, just patch it replacing "<glib/gtimer.h>" with "<glib.h>".