Log in, Find Merchant on Ship... What??

He probably fell off. NPCs tend to do that on space ships.

 

Through the floor?

 

Do you have a bed on your ship? We've found that to be the only common denominator when we've had that issue. My fiancee lost her chef and I lost my doctor. Another friend hasn't lost anything and has no bed.

 

I have...
Strange bug. I'd prefer it to stay there though. Occasionally my Doc slept in it and healed up.

 

As hansmorg said, there are different kinds of spawners, the one with a pickaxe (Tool spawner) spawns a tool vendor, the Doctor spawner spawns a stim merchant, the Cook spawner spawns a raw food merchant. Those are some of those you can find in chests (those I found so far).
You can also craft a villager spawner (doesn't sell anything) and a Guard spawner (weapon carrying npc).
Once a spawner is placed, a npc will spawn when you leave the area.

Also I once accidentally killed my chef. I died on the planet and when I respawned in the ship the attack animation I started before I died continued and killed my chef, I now place a door between my teleporter and the rest of the ship.

 

We think it might be OK if the bed is resting on the floor of the ship (not on a platform) but I don't want to test the theory out. I just don't place spawners on my ship anymore. I get the feeling people don't like the idea of making a 'home base' on a planet, but we set our home planet and make a small town for our spawners and build houses for ourselves too. Works out nicely with the new 'warp to hope' option.

 

It always was on the floor in my case.