Please find attached a sample solution where the last column in the HierarchyChildTemplate grid takes up all the available space. If you are unable to reproduce the behavior in your project, please share it.
the Telerik team
Do you want to have your say when we set our development plans?
Do you want to know when a feature you care about is added or when a bug fixed?
Telerik Public Issue Tracking
system and vote to affect the priority of the items.