Help: Objects not visible in preview when ID passed through parameter

Hi, I really hope to get some help no this.

I have noticed that when I follow the standard method of passing the ID through to a details page, many of the objects in the data resource are not visible when I preview the app. This is both on mobile and PC.

I have had this issue for sometime but managed to work around this by creating individual parameters for the items that don’t consistently show up or don’t show up at all.

However, only text can be passed through a parameter. So my comments section, which is a list of objects won’t render at all (though it’s visible in appgyvr) and I cannot pass it through a parameter.

Has anyone had this issue? it doesn’t make sense as to why some things show and others don’t when clearly the data is populated.

Note that the debugger gives me this error:
source.uri should not be an empty string.

Any help would be appreciated. Thanks.
appgyver issue