"Put ezfla_up.bin on the root of the ?SD and hold R when booting, delete ezfla_up.bin afterwards if you feel like it" is a pain in the arse? Maybe if you go into the deepest, darkest recesses of skin making it gets to so but for the most part even skin making amounts to "put ezfla_up.bin file that uses the relevant loader into folder, put skin pictures/files into relevant folders, press build in tool, do normal update method with newly made ezfla_up.bin".