The given process model was built with a NWDS or development track of a higher version than the target runtime. Revision number of built process model: 4.4. Revision number of process runtime: 4.3. Please refer to SAP note 1600131 for details.
The error is self-explanatory. Use the relevant version of NWDS. From note:
Release 7.31 SP6
Compiler version: 4.3
Runtime version: 4.3