Hi,
Is the GW_PRINT defined with reference to DDIC type, where the DDIC definition has the relationship between the amount and currency fields set up? If not, please check Displaying Fields That Refer to Currencies or Quantities. The idea is: you have to set up this relationship via Global Definitions, "Currency/Quant. Fields" tab.
If that doesn't bring you further, can you create a test smartform illustrating the issue, export it as xml and attach here please?
cheers
Jānis