my $line = <DATA>;
my @wanted_substrings=();
#No Problem
#my $StartTag='START';
#my $EndTag='END';

#Error Unmatched ) in regex; marked by <-- HERE in m/TRicky\(.*?)
#my $StartTag="TRicky\\";
#my $EndTag="\\endTricky";

#No Error but no value VALUE
#my $StartTag="Next\$";
#my $EndTag="\^Next";

#No Error but no value VALUE
my $StartTag="Last\+";
my $EndTag="\+some";
 	  if ($line=~/$StartTag(.*?)$EndTag/g)
    {
       push(@wanted_substrings,$1) ;

 	  }
print join "\n", @wanted_substrings;
__DATA__
CharSTARTanotherENDCharTRicky\VALUEE\endTrickyNext$VALUE^NextLast+VALUE+some