1.Can you raise barricades in the tunnel track? Eg. at the good Dr's office?
2. It seems you cannot research or heal without science heroes. Does this mean the research ladder is dead in that case? Seems harsh not being able to heal.
I don't have the rules in front of me, but I'll try to answer from memory.
1. Yes. You can build a barricade on any track. Just remember, only one per track (i.e only one in the tunnel) and they don't do anything if placed in the town areas or town center.
2. You need a science hero to research. Don't fear though. You just need to survive until a new hero arrives and select a science hero to get to work in the lab!