Grove Shield with Arduino MEGA

Projects General Guidance
1

I actually made the post here in the seeedstudio forum but apparently its not a very popular forum:

I have gotten the Grove shield to work with the UNO with the dust sensor example. Now I want to do 2 things to complicate the project a bit:

  1. Add more sensors. 5 more sensors to be exact for a total of 6. The Grove Shield v2 has 8 digital ports, one of them the UART port. So out of curiosity Im wondering what I would need to do if had to add more than 7 sensors since that means I would be out of digital ports?

  2. The dust sensor sketch from Grove ( http://www.seeedstudio.com/wiki/Grove_-_Dust_Sensor ) talks about pin 8 and I was wondering if thats why we are told to connect the dust sensor to D8. More precisely the question is, does D8 on the grove shield mean that it uses Pin 8 on the Arduino board? So D5 would mean I have to connect it to pin 5?

Thanks