yes, those are the only two ways you can set the Text of a element. I hope this won't get in the way of your TestCase.
Minimizing/maximizing a browser shouldn't affect the way the WebAii Framework locates elements. The problem is likely caused by your find logic. Would you please paste the logic that locates this element as well as the HTML code for this element. This info will allow me to analyze the issue!
Hope to hear from you soon!
the Telerik team