I’m using Sencha’s Ext Designer to create their Cars example, but I can’t find the correct property to change the Price column so that it renders like a number.

The code behind it refers to an xtype, but this property is unavailable in the designer. There is also no way to edit the code in the designer tool.
How do I change the xtype of a column through the designer?
I’m using Ext Designer Version: 1.2.2 Build: 48.
Right Click on the column in the grid, mouse over the Transform menu item and choose the type you need. I see the following choices: