VB Script for DATALINKS

HI Good Morning,

I am working on IFIX migration system from FIX 32 to IFIX 5.5 with FIX Desktop. I am new to Fix 32, IFIX and VB scripting.I have one issue here, probably a simple one for people good at IFIX.

I have two DATALINK fields and a button on the screen. In First datalink field, Operator enters the number in Feets (Ex 200 FT) and in second data field, operator enters data in inches (Ex 8 inches).After entering theses values on the scada,there is a button next to these data fields,"Enter data" Button. When operator click on the button,
the data entered in the DATALINK fields will be written to the PLC and it will be displayed on the DATALINK field until operator changes to different values.
This is working in FIX 32 but in IFIX it is not working.
I am able to enter the numbers in the datalink field but once i change the picture, these values are going back to zero.And whatever value i have entered in Data field is not getting updated in the PLC.

Can some one help me how to write VB script for this.ABH driver tags (Direct PLC tags) are used for Data link fields and button.

Thank you,
Pavan