Scenario Difficulty Rating System?...and other ?'s

[Double_Deuce]

I did a fairly small and short campaign called Mexican Drug War - 2005!

Its over at Strategy Zone Online but you may need to register to DL it. The link in red above will take you there. I think I also uploaded it to the Wargamer Scenario Depot as well.

[JoJo_Pumpkin]

I started the U.S. Marine campaign. And it was laughable. I played through the first mission "Operation: Desoto" I realized I needed some vehicles and would you believe EVERY one of my vehicles was deemed immobile in less than 3 turns! HAHAHA! If it wasn't for those dang mines, spider holes and earthened bunkers, I might have done better! Fortunately, I had some mortars and LAW units to help with those troubles. I managed a draw in the first battle.

I tried the "Kiowa down Scenario" but for some reason it "failed to load".

I'll look into the manual to see what I'm missing about loading scenarios.

[Pepper]

Your mentioning spider holes reminded me that the USMC campaign can be a little tricky.
Try to get Kiowa down to work. Thats a good intro.
Play Wild Bill's "Over There" its a really small scenario, again it will force you to focus on small squad tactics.
Double Deuce's drug war campaign is also an excellent suggestion. In fact that campaign is probably a little better for starters than Silver Lions.
I'd mostly suggest playing the small scenarios, and play them over and over until you learn the basic tactics of engagement. Then play the larger scenarios and campaigns.