** ERROR 129054 ** The piston volume is negative. Enter an appropriate value in the Gas-assisted injection controller dialog and re-run the analysis.
The value for Piston volume must be a positive number.
Right-click on the gas entrance and select Properties. Click Edit... and when the Gas-assisted injection controller dialog opens, confirm that Gas injection control is by Gas volume controller. Click Edit controller settings... and enter a positive value for Piston volume.