It's barely changed from 1st edition.  In fact I can only really see two changes and two mistakes that carried thru.

Changes. 

1.  The ranges now include multiple long ranges.  Close/melee range, nearby, far.  Now there is far(2), far(3), etc.  more range bands.  I'm ok with that. It's optional, but they needed a range band for enemies on radar sensors, but still out of weapon range.  This was something I had already house rules for.

2.  Weapons are now classed as light melee, light ranged (1 damage), heavy melee, heavy ranged (2 damage).   

3.  Damage reducing gear doesn't have a minimum.  It used to not stop that last point of damage. Now you will often take no damage.

Problems that still persist.

1.  No character improvement from experience. 

2.  Gear not well explained.  Read carefully.  Pay attention to the "and" statements, or "total damage" statements. 

For example, in the combiner ability (Voltron/Decepticon Devaststor) it mentions that the merged bot can use each sub-robot's abilities, but only once, and quote, "once per turn, as per usual."   Uh, what?   The book never says that anywhere else.  Now, it's a good rule if you ask me.  It will stop players from spamming their best ability, so I'm using it.

I'm thinking that editing isn't Gallant Knight Games strongest department.

Overall it's a good book, but I'm also underwhelmed because it's just slightly better than the first game.