I have the same configuration as your example. It looks like the printing works. However, the label comes out without any data. I used the ZPL viewer to make the layout and it should be within the printable area of the paper.
^XA
^FX Box containing Item number and quantity
^CF0,30
^FO20,500^GB320,220,2^FS
^FO140,500^GB2,220,2^FS
^FWB
^FO45,535^FDItem Number^FS
^FX Vertical line between Quantity and Unit
^FO140,575^GB90,2,2^FS
^CFA,45
^FO80,535^FD$ItemId$^FS
^FX below is for Code128 Barcode BatchNo.
^FO20,165^BY2
^BCB,130,Y,N,N
^FD$InventBatchId$^FS
^FX Quantity and Unit text area
^CF0,30
^FO150,600^FDQuantity^FS
^FO150,515^FDUnit^FS
^CFA,30
^FO195,600^FD$Qty$^FS
^FO195,520^FD$UnitID$^FS
^FX Horizontal line below Quantity and Unit
^FO230,500^GB2,220,2^FS
^FX Product dimensions
^CF0,20
^FO240,660^FDConfig:^FS
^FO240,510^FD$ConfigId$^FS
^FO265,668^FDColor:^FS
^FO265,510^FD$InventColorId$^FS
^FO290,676^FDSize:^FS
^FO290,510^FD$InventSizeId$^FS
^FO315,670^FDStyle:^FS
^FO315,510^FD$InventStyleId$^FS
^FX below is for Code128 Barcode LicensePlate
^FO175,40^BY2
^BCB,140,Y,N,N
^FD$LicensePlateId$^FS
^FX below is quantity of labels to print
^PQ3,0,1,N
^XZ