Ive built a army of medium sized fighters, sent these to attack planet and kill of remaining ships - DONE OK

built TRANSPORTER, huh only hold 1000 men ? anyway send them in. the first time i clicked the transporter to attack planet I was given option on what to do, but my 1,000 to their 10,000 looked doomed.

so built LOADS of transporters, now they are ALL hovering round the planet i want to attack.

BUT, i click transporter, and then planet and nothing happens, what am I doing wrong?