Hi Zetha,
Can I use other electronic components that I already have (from Arduino) with the mCore Board?
Can I use the makeblock sensors with the Arduino board?
Above two questions are belong to personal DIY project, sorry that we don’t have the ability to provide suggest without test. While you can figure it out by yourself refer to the info for mCore and the sensors in following links or maybe someone who has similar experience may help:
http://learn.makeblock.com/en/mcore/
http://learn.makeblock.com/en/electronics/
Can I program other Arduino robots with the mBot (scratch) software?
The mBlock software provide program block based on product principle from makeblcok.
Can I use a 9V battery with the mCore Board?
It is suggested to use 3.7VDC lithium battery(charger on board) or four 1.5V AA batteries (not included)
Can I use 3 or more servomotors with the mCore board?
Yes, you can use this kind servo for mBot: http://makeblock.com/mbot-servo-pack