To change the device mode between Winodws and Mac mode:
This applies to all devices that have Bluetooth - typically with a rev. 4.0 sticker.
Press and hold DPI(Cursor speed) + Paste - hold them down for 2 seconds. This will make the LED indicatiors flash for a moment.
Now let go of the DPI button.
While holding down the paste button, you can now press the DPI button to change mode of the device.
Windows mode: LED indicators will light from left to right.
Mac mode: LED indicators will light from right to left.
HID mode: LED indicators with light from both sides towards the middle.
Choose the mode fitting your operating system and you are good to go.