when you play battle of the coral attols, there are two hidden paths that helped me beat the mission. To get to the first one, you have to defeat the rocket squad. Then, go to the beach and defeat the heavy tank. Then,put your battlestation and bomber in sentry mode, then put your infantry in follow mode, and swim to the island with the three artillery units on it. The second hidden path is located on the western island. Go to the SOUTHERN beach (believe me,it matters) and go onto the island. Then, go to the cliff over witch the capture point is. Then, try climbing in different places. Eventually, you will be able to climb the cliff and secure the capture point. Hope this helped!
When you blow up a tank, recon or gunship, do NOT take your eyes off it. If you have good eyesight, you will notice that the dead soldiers will fall out of the vehicle. I tried this with a gunship and two Tundrans fell out of the sky. One of them landed on me. This cheat is not vital to beating the game, it's just hilarious to watch.
To destroy a gunship with a grunt, simply aim upward and......FIRE! This is easy but it may take a little more than a few shots to destroy it. Have missile vets helping out.
Light recons are more useful than you think! When you are in a light recon during a battle, back up just far enough that you don't get thrown back in. Then floor it! Aim directly for the enemy soldiers and run over as many as you can. You can wipe out quite a few grunts, flame vets, bazooka vets, and even assault vets if they aren't looking. I highly recommend using this in the Tundran campaign.