This website contains lots of goodies for Pacific General.

http://www.peachmountain.com/5star/PAG_index.asp

The two downloads I recommend are

The 5 Star Equipment File v2.3. Simply download this and unzip it into the data file in your Pacific General Game Folder. and

The 61 Scenario Pack. Unzip this into the Save folder in your Pacific General folder. Repeat, your save folder, not your scenario folder. Then when you go into the Scenario loading screen load them using the load Homemade Scenario button.

You have just added 61 new scenarios to Pacific General.Enjoy!

And yes, I triec a couple of the new scenarios using the GOG version of Pacific General. They Loaded fine.

I am a long time fan of Pacific General. The best custom equipment and campaigns are East Wind Rain and US Campaign Replacement Scenarios (CRS) from the no longer existing Steve Strayer's Pacific General Armory website, but you can still download them using the Wayback Machine:
http://web.archive.org/web/20080919211653/http://ourworld.compuserve.com/homepages/sgt_stryker/paccamp.htm