You can implement some hacks to changing the selection color, the main one being: http://yourpalmark.com/2007/08/13/ch...ic-textfields/

You need to download and implement the SelectionColor class, but I only know if it existing in AS3. So if you need AS2, I think you're out of luck.

But what do you mean by adjusting the shape? You just mean what text is selected? If so, there is a method of the TextField object called setSelection.
PHP Code:
myTextField.setSelection(0, 10) 
That will select the first 10 characters.