Welcome to the board Alienboy.
First of all, simulator is indeed quite buggy. Don't try to rely on it in details. It will serve you until things go overcomplicated, but after that it tends to suck. If you want to know real situation, arrange a test game with a real battle.
1. This might happen if your weapons have reload rate of 2 or more. Then such weapon will fire once per 2 or more turns.
As for firing at unarmed ships, dunno, but I have a feeling that weapons on planet behave itself quite independent of WP strategy. This is my impression, though, and I could be wrong.
2. a) Other ships could be out of range; b) yet another simulation bug; c) it's a real bug of SE4. If you want to check this out - arrange a test game and combat, if you'll get the same results, you could proudly report another se4 bug
