We have endeavored to provide detailed errors/exceptions/warnings when SAM has not been configured correctly. If you see any of these in the Console Log, please read them thoroughly to try to self-diagnose the issue.
Some common issues that result in errors/exceptions/warnings are:
1) Missing Scenes from Build Settings Window (if using a Scene Chunk Streamer).
2) Prefabs have been placed in a subfolder of the Resources folder (Resources/MyAssets for example), but SAM has not been configured correctly to work with subfolders (more information about this issue can be found in the Prefab Streamer Section of the Chunk Streamers Chapter (scroll down to the Prepending Extra User Data sub-section.
3) Incorrectly named Assets. Remember that All Asset Chunks for an LOD Group must follow a common naming convention. This convention may either be one of the default conventions or a custom convention defined in a custom NamingConvention asset (detailed information can be found in the LOD Group Naming of the Streamable Grids Chapter.
If there are no errors/exceptions/warnings, then your issue is likely caused by one of two things:
1) An improperly assigned Player Transform (if using Active Grids). Take a look at the World Not Updating Section of the FAQ for more information about this issue (Improper Player Assignment sub-section).
2) An improperly configured Origin Cell or Origin Cell Position (found on the World Component). Remember that the Origin Cell is the Streamable Cell from the Base World Grouping that will be placed at the Origin Position, and that all other Streamable Cells are placed in reference to the Origin Cell.
Also remember that while the World Designer Tool uses the same Origin Position as the World component, it does not use the same Origin Cell. This can result in confusion as if the Origin Cell defined on the World Designer Tool is different than the Origin Cell configured on the World component, the position where your Cells/Asset Chunks are loaded in at using the Tool will be different than where they are loaded in when you enter play mode.