Can you have 2 instance of it running? The 2nd one could show USA session for example.

yes

Do you know why it cant be used on backtesting?

Does it also work on mt5?

Sadly, I could not get this product to work properly: not sure why. I followed all the instructions to the letter. All I got was three different coloured shadow boxes on my screen. It really didn't show me much at all.

I am still busy testing the indicator.

Excellent, very convenient indicator! Thanks!