Hi Korchev,
It's quite simple what I'm trying to achieve, basically a loading indicator that appears before and during the data load, then disappears and reveals the grid once the load has finished.
I apologise I didn't notice the Subtle renaming "RadzenGrid" vs "RadzenDataGrid" 
I'll take a look at the new one.
For the time being though (After todays sprint anyway) I've now come up with a work around. It's a lot more mark-up and code, but it handles the case quite succinctly.