I wrote:

There seems to be a problem if the initial number of rows in the data source is 1 or 0. If it is > 1, then new rows that are added are correctly displayed.

 
admin wrote:

We confirm the Grid component issue reported by jtara. We will resolve it in the next update.

 
I’m afraid that even in 4.5 there is still a problem. It is SLIGHTLY improved.
Now, it no longer fails with only one row.
However, a grid that is initially created with no rows still fails. You will never see the grid content displayed.
There are of course so many use cases for a grid that initially is empty, and then rows are added. We still have to start out with at least one dummy row.
I will write a support request. Just giving a heads-up here for others.