Userscripts.org

The userFormats is ignored because of a bug in the underlined line.

// Extends the video formats array with properties regarding the user configuration (userFormats array)
videoFormatsArray.userFormatsLength = 0; // Counter of the video formats selected by the user which are supported
videoFormatsArray.forEach(function(vf) { // Adds properties to each video format object

	// isAvailable will be updated by selVideoFormatAvailability or its initialization code (1: available, 0: not available, -1: unknown [request error], -2: not checked)
	vf.isAvailable = null;

	// userChosen indicates if the video format has been selected by the user, userQI holds the QI given to it by the user (higher is better)
	if (userFormats === null) {

		// userFormats is unavailable. The properties get their default values
		vf.userQI = vf.QI;
		vf.userChosen = vf.defaultChosen;

	}
	else {

		// userFormats is available. Tries to find the video format in userFormats
		if (userFormats.indexOf(vf.idx) != -1) {

			// The video format has been selected
			vf.userQI = videoFormatsArray.userFormatsLength + 1; // 1 for the first one, 2 for the second one, etc...
			vf.userChosen = true;

		}
		else {

			// The video format hasn't been selected
			vf.userQI = null;
			vf.userChosen = false;

		}

	}

	// Updates the counter if the video format has been selected
	if (vf.userChosen) videoFormatsArray.userFormatsLength++;

});

The line should read:
vf.userQI = userFormats.indexOf(vf.idx) + 1; // 1 for the first one, 2 for the second one, etc...

This is due to the video formats array always being passed as

[0] = FLV Low Quality -- This always gets userQI = 1
[1] = FLV High Quality -- This always gets userQI = 2
[2] = MPEG-4 H.264 -- This always gets userQI = 3
[3] = MPEG-4 H.264 HQ -- This always gets userQI = 4

whereas userFormats.indexOf(vf.idx) + 1 gives the proper result according to the user preference

For example: ["18", "6", "", "22"] will result in this

[0] = FLV Low Quality -- This gets userQI = 2
[1] = FLV High Quality -- This gets userQI = 3
[2] = MPEG-4 H.264 -- This gets userQI = 4
[3] = MPEG-4 H.264 HQ -- This gets userQI = 1

P.S: Sorry, I had to use the deprecated width element of pre to avoid border overflow since userscripts.org doesn't allow styles in posts.