Hello,
This bug should be very easy for your team to reproduce. When I click on an item in my gallery, I want to set a variable (gblMyItem = ThisItem), navigate to a new screen and display a form in View mode. However, the lookup field values are always blank. It will work when the form's Item property is set to Gallery.Selected, but I cannot use Gallery.Selected because I need other functionality on these screens which will only work with a variable. I have tried with the Form's Item property as both a variable or a LookUp() function call, and neither seems to work consistently. Note sometimes in the PowerApps editor, you will force the lookup fields to load and then it will appear to work, but if you publish the app and play it, you will notice that the lookup fields won't load.
Any advice? Lookups are a huge pain, this is just another chapter of the same story.
EDIT: I am using CDS as my data source.