What you might want to do is rethink your test design a little bit. The file that you are using for your test, you might want to make sure exists on all testing environments in some sort of standardized path/location.
Secondly, rather than trying to access the file using Start button and other such things, there are other methods available for working with files. You might want to look into aqFile, aqFileSystem and other such objects.
Thirdly, while when you record tests in TestComplete it uses co-ordinates based upon pixels, this is not necessary for "Click" methods. In scripts, if you call "Click" with no parameters or in keywords if you set the parameters to -1 for each, the "Click" method will click in the center of the designated object, regardless of screen resolution.
Without further understanding of the specifics of your test, this is the best suggestions I can give.
