Hi Rahul,
on top of what Sarah already said, I would only add that the whiteboard did not erase when moving to the second part of the exam.
I fully agree that it tends to slow you down; to prepare for that, I practiced with Microsoft Paint. In particular, I tried to practice drawing networks using a text box, because I noticed my trackpad was not properly responding when it came to drawing. Still slower than pen&pencils, but also better than nothing
Good luck on your exam!
Gabriella