To check assets before preparing the scene for rendering:
1. The final scene has been assembled, in which all the edits in the render settings have been made.
2. Check that all assets are specified in the scene (globally or locally). The main task of this check is to make sure that all data will be read. To do this, open the main menu Window> Project Asset Inspector. If some asset has an incorrect path, then a red cross will be shown in front of it. Depending on what asset was lost, you must either specify the correct path, or delete it. The final task is that in the Project Asset Inspector window, all positions are marked with green checkmarks.
3. Apply the command File - Save Project With Assets and specify where to save. After cleaning, there should be no errors that some file was not found. When saving on the hard disk, a folder will be created, inside which there will be a file of the same name and a Tex subfolder, into which all textures and volumetrics in VDB format will be copied (!). The rest of the assets (scenes in * .c4d format for Xref, alembics, Mograph cache in * .mog format, IES files, sound files) will be copied to the main folder where the project file is located. In this case, most of the paths to assets will be automatically set locally.
4. Open the Project Asset Inspector, and check that in the Status field opposite each asset there is a green checkbox and that in the Path field all paths to assets are local. If some assets are left with global paths, then you need to check them manually by opening materials, containers of alembics, etc. and see how these paths are indicated there. If the path is local, do not touch anything and do not pay attention to errors. If global, then edit manually.