From when must the shell construction be dry or sealed?

What exactly do you mean by base sealing?

Sealing in the area of the first row of stones adjacent to the concrete - e.g. with plastic-modified bitumen thick coating. In our case, the sealing was not done by the plasterer, but definitely beforehand...

Unfortunately, I still don’t quite understand where this base sealing is supposed to be. From the garage wall to the Poroton brick wall vertically? Meaning where the dark spots from the water are visible now.

My architect also says that the moisture probably comes from the garage roof. Currently, it is being sealed.

Hopefully, this will help.

This is how we solved it. The house has Ytong blocks as walls. The first rows of blocks were still given two coats of sealing slurry by the mason. For three meters on the east side, the house and the concrete garage lie wall to wall. Therefore, this area has neither sealing slurry nor plaster. That’s not possible. You can’t get to it. That’s why the joint between the house wall and the garage was sealed vertically with MS polymer. Horizontally, in addition to the slurry, a galvanized L-shaped steel strip was applied, fully glued with MS polymer to the wall and the garage roof. So now it is completely watertight. Karsten

Now that the transition from the garage roof to the house wall has been sealed, no more water has entered the house after rain.

The question is now whether I need to let it dry or if the plasterer can continue with the interior walls? According to the plasterer and architect, it can continue seamlessly...

Actually dries outward. And the plasterer doesn't slap enough plaster on the wall anyway.