Good start! Looks like you're being quite thorough here.
Did you run all the angles in the same campaign? I'd usually recommend sticking with the 1 angle per campaign rule - it makes the data easier to analyse.
In answer to your questions:
1) Yes, it's still data. High CTR but no conversions can mean that the angle's appealing but the offer sucks rocks through a straw. It can mean that the placements that got most of the clicks are bot-tastic. It can mean that you're using a clickbait angle that the offer doesn't carry through.
2) Yes, absolutely. A few conversions but not enough is the canonical situation where you should start testing a lander stat!
3) That's a very good sign - you're already in profit. In terms of optimising specifically for that placement - do you mean starting a new campaign targeting just mobogenie?
4) CPM is how much you're paying for a thousand impressions. CPC is derived by combining CPM and CTR. CPM, however, is your base metric for cost. See
5) Yup, that's looking pretty promising (aside from the top placement). I'd keep testing unless the volume's dropped off a cliff.
6) The creatives look good! You're testing a wide variety of looks there. Are any of them animated?
7) The offer's promising - ish - but you're going to need either a much stronger angle or a converting lander. I'd run another angle with this offer but also test some different offers. I wouldn't recommend jumping ship on Decisive yet - Decisive can be expensive, but it's definitely possible to get to profit there, and you're better to focus rather than try to learn a bunch of new interfaces.