Welcome, @Gillian_Durham! This could be a good app to take a look at in office hours, if you're interested!
What type of component is cageInventory? The Mobile product doesn't have a table component, so you may need to remove .selectedRow.data from your dynamic references. You can use the state tab to see what properties are available.
Where are you putting the css? The mobile html component doesn't support CSS classes, so styling would need to be in-line:
If cageInventory was a query that returns a single object, you could do something like this:
The download utility expects the following params:
This post might be helpful.