Are there differences in the motor databases of S300/S700 and S400/S600?

Yes. In the S300/S700 motor database (MDB) there isn't a single dataset per power stage and feedback. The parameter values are calculated depending on the set FBTYPE out of the same rough data. Criteria for a valid motor for the power stage is now:

0.25 * DICONT <= MICONT <= 4 * DICONT. 

The motor databases for S400/S600 cannot be used with S300/S700.