Installation Guide:
Copy the vortex.pak file into the Flash Tool Folder
Connect your Tablet to your PC via USB (use the "upper" USB port)
First press "RESET" and then hold "MENU" + "POWER" until an VDFu USB device gets recognized by your PC
Launch the Flash Tool
The first setting reqires you to select an .INI file depending on how much RAM your device has. Use the file ending with 512M.ini if you have 512MB RAM or the file ending with 1G.ini if your device has 1GB RAM. (To find out how many RAM your device has, look into your manual.)
The second setting reqires you to choose your vortex.pak
The final setting is a radio button, indicating if you want to flash the tablet itself (left) or to an external TF card (right)
Press the button in the lower right to start flashing
Some warnings will pop up, just hit okay
Wait until the flashing progress finishes
Turn on your your Tablet and enjoy