I've just got my controller working flawlessly with X-Input. There are videos showing how to do it in Win7 but I've never found a decent tutorial written down that's easy to follow. So here's my crack at the guide I would've liked to have when I was setting up.
Check the version of your Bluetooth device.
If you're having issues reconnecting the controller, try a device using Bluetooth 2.0 or up. Logitech Bluetooth adapters can be installed as a Bluetooth devices if you hold the connect button when you first insert it. (Odd, but useful if you have some Logitech devices already)
Find your hardware id.
If you haven't installed your devices Bluetooth drivers, do so now.
Go to device manager and right click to properties on your Bluetooth driver.
On the far right tab, click hardware id on the drop down box and copy/paste the bottom value somewhere.
Close the properties window.
Uninstall your Bluetooth driver and unplug your device.
Start installing the Toshiba Bluetooth Stack.
Once it gets to the point it asks you to plug in your device, do not plug it in.
Open (Toshiba Bluetooth Stack directory)\Drivers\tosrfusb\tosrfusb.inf in notepad.
Ctrl+f your hardware id. If it shows up, skip this whole step.
Copy the bottom line of the [standard] list and paste below it.
Change the number to be the next consecutive number and copy/paste your hardware id from earlier over the hardware id at the end of the line.
Copy this line and paste it at the bottom of the [standard.NTamd64] list.
Copy the last line in the file and paste below, change the number to the next censecutive number and give your device any name in the quotations.
SAVE (in multiple locations in case you have to redo this part)
Plug in your device
Click OK in the Toshiba installation once the device is recognized. Let all drivers install.
Restart your PC when prompted.
Install Vjoy
Once vjoy is installed(may need to reboot again??), type configure vjoy in search and open it.
Under basic axes, you want x, y, z, r/rz/rudder, u, and v.
Under POV Hat/Switch you want Continuous and 1 POVs
Number of buttons: I normally just go with 17 but you can go with less.
Connect your controller
Double click the Bluetooth logo in the taskbar.
Follow the instructions to sync the controller, press the sync button on the controller when asked.
Open WiinUPro
Click the check mark next to your Wii U Pro controller and choose joypad in the drop down box then connect.
Set ZR to +U joystick axis and ZL to +V joystick axis (if you plan on using Xinput enabled games)
Go to tools and open game controllers.
Highlight vjoy and click properties.
Go to settings and calibrate.
Use the left stick for the circles and press the B button to continue.
The Z Axis is up and down on right stick and Z Rotation is left and right on that stick.
Use ZL for U axis and ZR for V then finish the calibration
Congrats! Your controller is now configured as a basic game controller in Win7! See below for how to enable Xinput.
Open regedit.exe
Change HKEY_CURRENT_USER\system\CurrentControlSet\Control\MediaProperties\Joystick\OEM\VID_1234&PID_BEAD\OEMName to "XBOX 360 For Windows (Controller)" without quotations.
Repeat in the HKEY_LOCAL_MACHINE directory.
Exit regedit.
Connect your controller, then open Vjoy and configure to the same as above, then open WiinUPro and configure to the same as above, minimize it.
Download x360ce and the libraries that correspond with your machine (go with 32bit then 64 if 32 gives you trouble)
Extract everything to the games install folder, where the .exe is. (you have to do this with any game you want to play with this) Open x360ce and click OK to recognize the game then save and exit.
Open x360ce.exe again and click OK on everything. Set the left Trigger to Sliders\Half\HSlider 1 and the right slider to Sliders\Half\HSlider 2.
Set Left Stick Axis X to axes\Axis 1 and the Y axis to axes\inverted\IAxis 2
Set right Stick Axis X to axes\Axes 6 and the Y axis to axes\Axis 3.
Use the record drop down option to set the remaining buttons, then save and close. Whenever you start the game, x360ce will open as well.
ENJOY!