How do I move elements and hide (delete) elements on SAP screens?

Using GuiXT Script Editor Pro this becomes a simple drag and drop operation:

Select the element (or groups of elements) you want to move. Drag the elements to the desired location

To delete elements, simply select the elements and press the del key.

Without Script Editor Pro:

Navigate to the screen you wish to customize

Click on Edit->Script to launch notepad with a file name specified. Make sure that you use the file name GuiXT suggests.

To position elements, use pos command

To hide elements, use del command

Please read the GuiXT and Script Editor Pro tutorials for further explanations.