Nothing you've written will cause your CGI script to die, hence, assuming your script generates nothing on STDOUT or STDERR, nothing will be output to the browser (via CGI::Carp::fatalsToBrowser). To get a textual representation of any errors, try something like...

my @out = `C:/BatchTest/test.bat`;

die "@out ($?)" if $? != 0;
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Check the Apache server logs - they may (or may not;-) provide some indication.

Is Apache configured to 'recognise' the directory containing the target script i.e. C:/BatchTest ?

If so, are the permissions on C:/BatchTest correct ?