If you want an easier time for wars, for you and the AI, then this is quite simple. You can replace the file within this zip
within the current one of your game installation. The directory you are looking for, provided you did not change the default installation directory is:
C:\Games\Pride of Nations\VGN\GameData\Diplomacy
Hopefully, if you did change the default directory, you can find where your game is.
So in this 'diplomacy' directory, you'll overwrite 7-Declare War.dpl with the one I provided here.
I did not felt to upload a one gigabyte 'quickfix' for a file weighting less than a kb, so excuse the hand crafted manipulation. The plan is to have anyway only this limitation (you need now 4 imperialism to DOW, not 7 as of 1.04.2) only applies to the AI anyway. So we will post another QF with a new executable doing that.