I love SW3D BUT I find the way it handles background pictures very unhandy.

Is there a plugin or something which makes handling backgrounds easier - drag and move, tilt and adjust?

I have a property, which is tilted and spreads over several levels and so on... I achieved to draw it more or less correctly the first time but the problem is, I have now a more precise plan but it is for me almost impossible to integrate the new plan...

Pics:
https://workupload.com/file/KA8gfyxhUcv
https://workupload.com/file/bTDyDjfw5cT
https://workupload.com/file/cqAfvQTeePA

This is the best I achieved and I do not get the system, it's try and error
https://workupload.com/file/2EaJLHH9b7C

I am open to ideas