We're all familiar (I think) with the problem that values are set on comboboxes before the store loads meaning that you end up with the value displayed in the box instead of the text you want. The solution is to call setValue after the store loads. But, of course, that isn't always appropriate. You might want to use the 'value' config, or call setValues when your Dialog loads or something of that sort.

If ComboBox.js were modified to add an onLoad event to the store when the combobox is constructed, then this would solve the problem. Something to the effect of:

Code:
this.store.on('load',this.onLoad,this);
....
onLoad: function() {
 this.setValue(this.getValue());
}