VMA03 and Arduino Yun

I recently burned my Arduino Yun after plugging in the Arduino Motor Shield R3 (connected to a 12V power supply) because the Arduino Yun has no input voltage regulator on the 5V pin (unlike the Arduino UNO).

Actually i need more voltage to drive a motor (MFA 919D1481) which needs 15V in my case.
How can i safely connect the VMA03 to the Arduino Yun without burning it?
I think i have to power the Yun separatly via 5V USB and connect my 15V power supply to the VMA03 shield. Do i have to remove the 5V pin from the VMA03 shield to prevent loop through the 15V on the Yun?

Question update: Is it possible that the VMA03 is not able to power the Arduino Board?

Thx for the help.

So the question seems to answered. After heavy expermimenting i can truely say that you can use the shield with the yun. But you cannot power it through the shield so you dont have to care about overvoltage. On the other hand you need a second power supply like for your yun.

Another problem occured right now. While using the VMA03 on the yun and another Arduino Uno connected via I2C, the configuration seem to freeze both devices after an unknown period of time. Without the motor shield the I2C communication works fine.

Do both shield have different addresses?