For everyone who has similar problems or SH3D becomes too slow.
I have now done the following:
1. 1. Unused libraries from \ Users \ Username \ ETEKS \ SWEET HOME 3D \ Furniture \ Unused libraries from \ Users \ Username \ ETEKS \ SWEET HOME 3D \ Furnic \ secured somewhere else and deleted ...

@Puybaret, first of all thanks for the answer.
I was able to move my own furniture but how do I get the other furniture in the venue Library Editor?

Is there a way to reorganize the furniture catalog?
I mean to move furniture to another category or remove furniture from the catalog.
My project has now grown very big and I hope that it will be smaller.
Does anyone have a different idea to reduce (650 MB)?

Regards Klaus

@Keet
Thank you very much

Can someone tell me how I can produce a ramp 100 x 100 x 0 - 30 cm ?
Would like to make a slight increase in the garden.
Regards Klaus

Gruppierung aufheben --> Umschalttaste gedrückt halten das neue Objekt markieren (die anderen Objekte sind ja noch markiert) --> rechte Maustaste --> Gruppieren

@ dorin thank you very much for your work !!
I tried to build a roof with the templates but it doesn't look nice.
https://www.mediafire.com/view/gvzdu3kp2knswo3/Screenshot_2022-11-14_112036.jpg/file

Supporting walls or the right wall heights have created (screenshot 2022-11-13). Or do you mean ...

@dorin, thank you very much for yours Effort.
I selected the walls and not the rooms !!
Now the roof generator works !!
So now I have my next problem - the shape of the roof.
I took some pictures and uploaded.

https://www.mediafire.com/view/jlwwbllnq6hb6d2/IMG_3652.JPG/file
https://www.mediafire ...

You are right that is very detailed, I just stand too stupid to generate a roof. The roof generator is gray and I don't know what I'm doing wrong ??

@dorin, first of all, thanks for the answer.
I probably make a mistake, I still don't manage to activate the roof generator.

I did the following:
1. 2nd floor selected
2. All walls marked
3. -> Tools -> Autodimension
4. Roofenerator is still gray ??

Would it be possible to explain the step by step ...