Sense is, as you know, a launcher and an app collection. They're very heavily integrated - closely tied to one another. If you look in applications management, you'll find that Mail for example has its own revision number and so forth like Locations, but it's tied to the Sense version as well.
Under the hood, in files you don't see, is Sense's various glue layers (the framework) - software tying their apps together.
Last year's One X had USA and non-USA Sense versions thanks to a silly Apple lawsuit that they could only win in the USA. Our apps lost some features. Rooters quickly discovered that bringing in UK versions of mail and messaging apps didn't work - glue layers were different. Our development community had to decompile hidden files and tinker there in order to get the features working in the apps you can see.
My point -
After you're rooted and have a full nandroid backup as a safety net, drop me a line. I'll help you get to the old Locations app (without disturbing her Desire S) and walk you through laying it in as a system app, if you don't know how already. It's not difficult.
With a good backup, it's certainly worth a try. But if it's tied to its Sense framework, per usual, it's not going to work. If not tied in that way, you'll get lucky and Bob's your uncle.
Sense is actually put together in a very cool way, and it shows in its feature performance year after year.
Meanwhile, if you can find a good Play Store app with the features you need, your life is going to be a whole lot simpler.