It currently has some quirks and bugs, but the author has put troubleshooting tips into the readme.
Arrow Key Repurpose
<Left>: Unindents current line or selection by one level.
<Right>: Indents current line or selection by one level.
<Up>: If the line above the current cursor position or selection is empty (or contains only white space), deletes it.
<Down>: Adds an empty line below the current cursor position or selection.
There are aliases for shift-arrows too, check the documentation for more details.