Hi, havenswift-hosting.
You can download EE 1.7.1—see EEWiki:// HowTo Download 1.x Version of EE
I’d recommend you get everything working correctly in that version first. If you look at the path.php file, you’ll see where EE placed the system folder, and what it was named. It would be easier to rename the system folder to match the old system folder.
As far as licenses go, EllisLab can’t really assist in the issues between your client and their previous host, unfortunately.
Does that help?