I have finally connected my Boost Gauge (with thanks to a few pointers from previous threads), however, when my car is switched off the reading sits at 0 as expected, when i start the car the gauge goes into negative. Only when i acclerate can i get the gauge to read above zero, when i floor it i can get to read around a positive 10 psi. My question: Is this normal?

Any help appreciated

yup, how it should be

Unfortunately it's normal and is caused by pressure drop in the intake system which can be measured as negative boost - it's a drop in air pressure to below atmospheric.