Smart delete is one of our addons to improve the usability. It works only in Edit mode. That’s not a Blender feature. And the problem is, it works just fine here. So nothing to fix ^^
At least i have my answer now. You did modifications to the keymap. When it deselects instead of deleting, then you have most probably an overriding problem for some hotkeys, in this case select/deselect.
Have you tried to reset to factory defaults and start from scratch? Does delete work with the factory settings?
Note that when you do some modifications and save them, then uninstall Bforartists, and reinstall it, then this modifications are still there. They are stored at your PC in a settings folder. And not uninstalled. We talk about the content in a path like this. I hope it is the right one, i don’t have a Mac:
/Users/$USER/Library/Application Support/Bforartists/2.79/
The Bforartists folder does not exist after a new installation. It gets created when needed. At least at Windows. Dunno how it works at Mac. Anyways. When you save a file, then the history gets created here. When you save your user preferences, then a blend file gets saved there with the changed user preferences. And when you save the startup file, another blend file gets saved here with the new settings and adjustments. Here you will also find addons that are installed afterwards. And keymaps when you create a new one.
To make sure that really all old settings are gone, simply delete the Bfoartists folder.