[Merchant ships bug?]

I had this same issue. Could not buy or sell, message said I needed to get closer. I gave up at 0.01k though as I didn't want to crash into him.

[Adding crew.]

I know if you open the build menu you can see crew quarter size and crew requirements in the stats on the right. Might also be displayed in your Ship menu on the Crew Tab but I'm still learning too so don't hold me to that.

[How to salvage wrecks?]

You can chop up wreckage with a mining laser and there is a very small chance of getting a turret or ship system, but no resources.

[Newcomers, introduce yourselves here!]

Been lurking for awhile. Looks like I am going to get sucked into this game so Howdy, all!  8)

[No one sharing there Ship Creations?]

Things are still new. There are a couple of folks who have shared their designs. More will come.