Is it possible to pause my running NXOpen-process and interact with NX? (e.g. move some points)

There are some functions that will essentially pause the code and wait for user input (selection functions, message boxes, etc); but I don't know of any way to start a journal running, pause it, edit existing objects (or create new ones), then resume the code execution.

Can you give a better description of what you are trying to accomplish? There might be a different way to go about it.

You got what I mean. I tried to pause my code using messageboxes, but when a messagebox is open, there is no way to move some sketch points (for example) because there is only focus on my messagebox.

Correct.
I suggest moving the objects before running the code.

Okay that's not possible in my case because my code is creating a sketch with one line and the user should be able to correct the endpoint of the line interactive while the code "waits". Interaction is no problem but to stop the code while interacting is possible might be my problem.

I believe there is a function that will let the user select or create a point. Perhaps you could prompt the user to select/create the necessary points rather than moving existing points.

I will try it ;)