Hello,
It is expected. In such scenario either you change the Mouse Click commands to click relative to Window or use Manage Windows Control command to directly access Windows UI objects like Text Box, Drop Down, List Box, Radio buttons and more. When you use MWC, not only your task is independent of screen coordinates and screen resolution, but it can also run in background.
Please find demo on Manage Windows Control (MWC) at,
http://www.tethyssolutions.com/MWC_Demo.html
Hope that helps.