Interfaces 101: Build Forms and Other Interfaces Support

Hey, 

I am working through the Appian Developer Course. 

I have come across an issue on build an application step 8, I'm hoping to get some help with. 

The image below shows the step I am currently working on (.8 on page 6)

The task is to replace the category, status and condition numeric values with the values from the look up table created in an earlier task. 

I have not been able to get this to work, only the null value "_" shows on my interface. 

The relationships have been checked multiple times. 

Any advice on where I have gone wrong would be much appreciated. 

Many thanks