Upgrade OS Property 2.7.3 to 2.7.4

How do I upgrade 2.7.3 to 2.7.4?

Do I upload the whole 2.74 package and install it over the 2.7.3 version?
Wouldn't this erase any custom changes I have made?

Why is there no upgrade package that only contains the files that have changed?

Thank you.

Hi Marty,
If in new version, we only fix the errors that come from previous version, we will release both new installation verion and patch version. But in OS Property 2.7.4, we add several new features. And some of them need database altering. So we can't release the upgrade package as your idea.
You only need to install OS Property 2.7.4, all your existing data won't lose
Thanks
Dam