Most of the time, I use NotePad++ to open programmation related files (cmake files, xml files...), and it is the default program to open most text file formats in windows.
So, the fact that astrogrep uses notepad.exe instead of the system configured file opener is a major drawback for me (for example, I have a few text files with UNIX file endings, which are not correctly displayed by notepad.exe).
At the very least, if it's impossible to get the information about system configuration, could it be configured directly in astrogrep?
This is completely customizable via Tools->Options menu. Then select Text Editors and setup your preference. This also allows you to use line/column parameters on the command line if your program supports them.