You probably already have your solution by now, but just in case try:
lowerThird.GetObjectByName("Text1",out textObj)
textObj.Text = editName.Text
I haven't used C# before, but I think when you are trying to cast baseObj that is the problem. You can use "GetObjectByName" directly on different types of objects, not just xpBaseObject.
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Azathoth
Son of Cthulhu
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