How to fix this totally disarrangend data grid?

On a quick look, I saw that you manually added some extra DataRowPanels, and I think that is likely the source of your issues. Have you read through the Docs already? Customizing DataGrids in the way you seem to be trying to do can be tricky. It requires an understanding of their structure: Anvil Docs | Data Grids

I wasn’t able to run the clone of your app because it was lacking a dependency. See here for how to share a clone link that includes the dependency:

Or if you’re using the Beta editor - make sure you tick the box “include dependencies with your clone