The article here covers all of the changes to the two editions. After playing CV I can see why lots of the changes were made.

You can download it and the add on scenarios here .

Some highlights Maps-:

 

Search –

 

Counters added were substantial as CV was not yet designed I think. So an additional few hundred information counters, break downs and tweaks to some unit capabilities. As well as many new ships for boths sides to cater for nearly any conflict in ’41-42 period of time.

Search and shadowing were enhanced to reduce certainty.