Keymap click-drag direction has some issues, mostly has to do with more directions than people want or need. This gives 2 additional flavors (left v right and up v down) without affecting the current 8-way one. I tried making 2 more enums for direction, for the purpose of reducing the available options, but it wouldn't set in the keymap without creating a new keymap item first. So I detoured around that by making some operators show up in the keymap in place of the direction enum.
There is the possibility of a user having non-applicable directions assigned to in their keymap> In this case I put a warning to let them know that there is "no direction". Not much good unless they are going to go looking at every possible occurrence of this, though.
Lukas Sneyd