[Rules] 2nd edition Vs 3rd

[qwirz]

I got a BoB 2nd edition unpunched in a Trade.
I've not yet played it and I'm reading the third ed rules.
I see some changes.
What I ask is: can I play this straight out of the box with 3rd edition rules?
Charts and tables are different and I downloaded em fom the AP site, but do the Scenarios need some adjustments?
Do playing them with the 3rd ed rules affect balance in some way?
Is anyone aware of this?
Thanks

P.s. I crossposted on the BGG too.