The size of .EXE files generated by XLS Padlock is expected because XLS Padlock produces stand-alone EXE files (3-4 Mb) that must work with different Excel and Windows versions. They also use full Unicode support, VBA interpreter and this has a “price” (large size). Finally, EXE files have got anti-piracy protection which contributes to the size too.
If you don’t use our advanced protection features, you can disable formula protection and you’ll get a smaller EXE file.