For the Yavin mission, just send a few TIE Fighters to the area where Veers crashes. You are then able to control him like any of your units. You should then use the TIE's to clear a way for him to reach the evacuation zone.
If you think this level is bad, wait until you get to Redemption at Abridon pt.3. That nasty bad boy took me bloody days to get through!
If you go the Force Commander section of LucasArts, you get a description of each level and hints on how to complete them, albeit brief.
I've found that your initial unit selection in the hanger bay is crucial to how well you do in the mission. For instance, if you get pounded from the air at the start but didn't think to bring any anti-air units, it's probably best just to restart the whole level and change your choices in the hanger.