Once you are happy with the placement of your model, select the Exit Editing Mode button or click the ESC key. This will prevent any accidental edits to the model.
If you are using an LGS or LGSx you will need to Save the file in order for model edits to be preserved.
From version 2023.1 onward, all LGS files will be converted to LGSx when saving.
If you are using a Cyclone ENTERPRISE project the edits will automatically be save once you exit the model editing session.