Likewise, I first noticed this issue with the Victoria crater manned mission. The mission starts and the guy is falling through the floor. It does it every time without fail.

Was an issue with a particular build. Was fixed

Hmm... Victoria Crater is working now, but I just fell through the Kaiser Crater. So I guess the bug still exists.

Today's patch appears to have fixed the free-fall bug.

same problem here. just started a new career, but in the victoria crater there is no ground and my probes are falling through the floor.

Also, both of those screenshots were taken as I was falling through the ground

It happens for me too (on stable Steam version, not tested on dev)

Was a temporary issue

Fixed right after christmas

I've now checked all the manned maps and this issue affects the multiplayer Victoria Crater map too. I haven't checked the Space program map as I don't want to loose the vehicles I have there.
Forgot update clears saved games...have now checked the space program and this issue also affects the space program Victoria Crater map.

This was recently fixed. The tolerance was too low.

use mouse wheel for setting free-cam speed

OK, I found out what I have done wrong with with 3.b) I wasn't aware that the yaw button was in fact a modifier ... means I have to press both buttons. IMHO that is a bit illogical. Why do I have to press both?

But at 3.a) I can assign button 4*, and 5 (not 6, though) but it has no effect in the game what so ever. (But not to any other action since the game says it conflicts with the editor)

To the airlock problem ... once I had the rotation going I was able to wedge it in. The human building missions are in a desperate need of an tutorial.

I had a short look at the test version...inventory ... cool feature... the accidentally disassemble and the not able to disassemble will be solved once tools are introduced. With tool disassemble/assemble everything, without use it (when is possible).

No DEV -

If you can set the 4th mouse button it should work in game. You have to hold down the 4th mouse button and then move the mouse. to yaw/rotate the object, you have to hold down the 4th button AND the additional rotate button. While it might sound annoying or over complex the system works relatively well after after a short while.

As for the door, just don't build it for now. There's no need for it anyway at that point of development.

I have the exact same issue(about loading scenarios) and it has been like that for about 2 months, atleast. I have also tried to reinstall the game, didnt help. Have verifed the files in Steam, didnt help. Have tried many different thing, like changing graphics settings inside the game, and outside the game in the controlpanel for my graphics card. Nothing worked.
Have attached three screenshots to show the problem.
Iam running Windows 7 64bit btw.

Changing the equipment with the big Rover in Career Mode doesn't work either.

same issue here with both small lander and rover.

Was a temporary version issue.

There is a workaround for this right here:
http://steamcommunity.com/app/244030/discussions/0/35222218794446359/
Whereas you just switch back to the last stable build of the game ( before the release of multiplayer ).