I let the keymapper download a bunch of them from the server, but then decided to tweak them a bit, so I then modified them and saved my tweaked versions locally. So, for some games like Nova 3, I actually had a "server" variation of the profile, plus my own customized version, and they're all gone, both the auto-downloaded server versions and my tweaked versions. Anyways, not a big deal to re-create them (I can do it quite quickly), I'm just trying to figure out what happened.
And, I'll definitely implement your backup suggestions. I don't have my g5a with me, so I can't check, but I'm assuming "export" is simply one of the profile menu options?