The light cavalry movement ranges may affect your games in progress. If you were in a "pursuit phase" of a battle and you are on the running end of things then you might find your troops "caught" rather than escaping. Light cavalry now moves faster than heavy and medium (Dragoon) cavalry.
Other changes: PDT files were changed for artillery. In some cases longer ranges. This would affect you if you set up your forces where you were out of range of an artillery unit but now are in range.
I tend to not like to update my games midway through for the simple fact that the series has seen some real dynamic changes in the last couple of years.
If I were you: finish the campaign and then update.
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Generalfeldmarschall Wilhelm Prinz Peters von Dennewitz
3. Husaren-Regiment, Reserve-Kavallerie, Preußischen Armee-Korps
Honarary CO of Garde-Ulanen Regiment, Garde-Grenadier Kavallerie
NWC Founding Member
For Club Games: I prefer the Single Phase mode of play. I prefer to play with the following options
OFF:
MDF, VP4LC, NRO, MTD, CMR, PR, MIM, NDM, OMR (ver 4.07)