Sorry, I don't have a copy of the game to play and mess around with, perhaps one of our great members can offer a little more assistance 🙂
Thank you anyway
I solved the problem with the help of the video described above.
The game MUST be played in windowed mode. Select a resolution so that both windows can be seen next to each other. Then select a resource in the game with the mouse. Now you must NOT switch to the trainer with the shortcut keys ALT+TAB, but select the trainer window with the mouse. Now the value should be taken over correctly and you can overwrite it. Now select the game window again with the mouse and the new value should now be correct.
Thanks to all who helped me.
[Edited by kuru61, 2/17/2021 4:20:07 PM]