Embed canvas app in modeldrivenapp with lookup fields. The look up fields are not showing in the modeldriven app!! What am I doing wrong?

[Brutus]

I have 2 custom tables. There is a 1 to many relationship. I want to use a canvas app to clone a record. In the app there is a button that patches to a new record. But I also want to copy the relationship to the new record. But the app refuses this. Normal fields work fine. 

Even in a  normal labelfield it won't work embedded. In the canvas app Studio, it finds the correct value. But when I use the embedded app in the modeldriven app the values of the fields are empty??? 

I also tried this with the look up statement but still empty in modeldriven app. What am i doing wrong?

Thank you in advance!