I'll try to answer your questions before someone else jumps in ahead of me.
1. You can create a 'Warp Point' via the 'Empire Status' (Crown icon). Then in the Planets Constuctions window, click on the 'Set move to' and any ships built here will move to the warp point you specified.
2. The Colony types are used by the AI in determining what to build there. I usually turn that off via the 'Empire Status' 'Empire Options - Look for the 'Display select colony type ...'
3. A 100% Mineral Planet will give you 800 Minerals per turn, 110% would give you 880 minerals, 90% 720 minerals. Anby planet with low %s just build Research, Intelligence centres, Storage Facilities, unless you need the money.
When you are ready give PBW a go. That's the best part of SE IV.