Remap Gamepad buttons

[Rapti]

I've been trying to swap the gamepad's shoulder buttons for a better NDS VC experience. As per the instructions on the controller_patcher wiki I've created a file /controllers/gamepad.ini on my sdcard with the following content:

[Gamepad]
VPAD_BUTTON_L=VPAD_BUTTON_ZL
VPAD_BUTTON_ZL=VPAD_BUTTON_L
VPAD_BUTTON_R=VPAD_BUTTON_ZR
VPAD_BUTTON_ZR=VPAD_BUTTON_R

But I can't figure out how to activate the configuration in HID to VPAD's UI. I select the Gamepad on the left and press A, but then it seems to wait for a button press on a USB controller and nothing happens when it press A on the Gamepad again. Pressing + to apply patches sends me to the Wii U system menu without any buttons changed. I'm using Version v0.9k from the Homebrew App Store which I believe is the current version.
How do I make this work? Thanks in advance!

My Gamecube controller adapter is recognized and working just fine with this tool.