Don't count me
Here is the second training mission tips:
Sides: Left = Grass, Right=Desert.
Key concept: cover Rocket Laucher, scrifice Step BOts one by one to destroy enemy left turret and Heavy invaders.
Turn 1: Invade!!! Move in and destroy the left turret with Step Bots and rocket laucher. Move LAVs to maintain the line and completely cover the left part of the island. Recruite LAV near the road or on the desert.
Turn 2. Move Rocket Laucher out of range of the second turret, make one Heavy Invader hp =1 with step bots, create a complete line of LAVS to protect 1hp Rocket Laucher. Start destroing enemy scouts (if you can deal 4 damage to 2 targets it's better to deal it 2+2 than 3+1 - you are more likely to destroy both on the next turn) do not spend valueable Rockets on enemy scouts. You may allow 1 enemy scout to invade you - deploy gurelia and destroy it. Ignore the second turret - it has 9hp and deals 2 damage while 2 enemy scouts have 8hp, deal 2 damage and the first is destroyed after taking only 4 dmg. Buy LAVs. Maintain defensive line of LAVs.
Turn 3. By the end you'd have destroyed a turret, a HInvader and 3-4 scouts. If you still have 1 Step Bot and Rocket Laucher alive - everything is decided - you can win using only cannon fodder by now (took me ~6-8 turns (don't remember)