@urgendalai, it’s possible your situation is not identical to what Stacie was experiencing. But if your original raster has any negative values, then it might be the same issue.
Anyway, if you are still seeing a KeyError then you will need to add a row to the biophysical table for the keys that are listed in the error message.
If they key that is listed should be represent nodata, you can still add the row to the table – it will not hurt – but you should probably assign that value as the nodata value for your raster. In general, it’s always a good idea to have a nodata value defined, rather than blank.
If none of this works, then please send me your landuse raster and I will take a closer look. You may upload as an attachment here or send me a private message. Also, please include the latest logfile if you are still getting an error.