Update:
This simple regex would also work under vim instead of using macro.

s/\(.*\),\(.*\)\n\(.*\)\n\(.*\)\n/"\1,\2",\3,\4\r/g
[download]

Without using vim, under Unix, you can do:

perl -e 'my $data =`cat test.pl`; $data=~s/(.*),(.*)\n(.*)\n(.*)\n/"\1
+,\2",\3,\4\n/g;print $data;'>newfile.csv
[download]

Under windows, you can do:

perl -e 'my $data =`type test.pl`; $data=~s/(.*),(.*)\n(.*)\n(.*)\n/"\
+1,\2",\3,\4\n/g;print $data;'>newfile.csv
[download]