The Matias Ergo Pro keyboard has a control key where I usually type "b" (I type "b" with my right hand). Here's how to remap that key to a "b".
- Download Karabiner: https://pqrs.org/osx/karabiner/
- Install it
- Open the app and go to "Misc & Uninstall"
- Click "Open private.xml" to open the customization file
- Open "private.xml" in TextEdit
- Add the following:
- Save and go back to Karabiner
- Go back to the first tab, Change Key
- Click Reload XML (top right)
- Find "Remap Right CTRL to B" in the list and enable it
update: I just switched to a new computer (Mac OS Sierra 10.12.4 - 16E195) and Karabiner appears to open and run as it did before, but it's not actually doing anything. My right ctrl key does not work as a B anymore.
edit: Even after uninstalling and reinstalling Karabiner, it still does nothing.