The change log does say that it could potentially "break" some CIV-checked games ("may break some titles that use CIV"), but other titles should boot and play fine .
Simply run the installer (default.xex) with XeXMenu or FSD/F3 and follow what you see on-screen.
A JTAG/RGH system is region free and the majority of security checks are removed - this seems to be an issue with certain CIV-checked games (BLOPS 2 being one of them I believe).