What does it mean when my rocket says "Space above Rocket blocked"?

[SchlauFuchs]

Hi, 

The Problem is, I have constructed myself a rocket and then found that the engine is too weak to get to the destination. I try to replace the "Small Petroleum Engine" with the "Petroleum Engine", but the selection dialog shows "Space above rocket blocked" in friendly red letters. The space is of course not blocked above the rocket, at least nothing I can see. 

What could be the cause?

okay, found. The ladders left and right of the engine were in the way. Well, "above" seems to have no meaning in space.

[sakura_sk]

57 minutes ago, SchlauFuchs said:

Well, "above" seems to have no meaning in space

"above" platform perhaps..?

Maybe it should say just "Space is blocked" or give a red blueprint and "unable to build" warning or maybe there should be a way to see what is built before hitting "build" button

[SchlauFuchs]

the best from an UX perspective would be to highlight on screen what is a blocker.

[habuky]

I think the ladders left and right block the engine. Try in debug removing them.

 

[Sasza22]

Replacing modules is pretty wonky. You can replace them easily if they are the same size but if you want to fit a bigger module it won`t let you replace it. That`s the issue here. The CO2 engine is smaller than the large petrol one and won`t let you swap. You need to deconstruct the old one and then build a new one.