Some other newbie questions (mines etc)

[Power Man]

You should also design a transport that is classed as a Troop Transport. The Troop Transport has a default strategy of capture planets. The regular transport has Don't get hurt.
I usually build my Troop transports with more armor and one or two planet wepons.
I think that if you put troops on a regular transport in strategic play the transport will run to a corner and never land the troops.