For Mission 5, the bomb starts on a repair pad. Does this pad count for making the lava wall move faster?
In our game, yes. So the second repair pad is on the second tile.
Also, can we move the bomb onto a repair pad multiple times in order to get the health back up?
I believe, yes you can.
Can the health go above 5?
No, the mission dossier specifically says:
The Bomb can be healed multiple times per round, but cannot exceed it’s maximum health of 5.