Help with Mac app installs tracking

Hello guys

I am working for an affiliate network promoting their program. They claim that the install tracking is based on the file name. I used to download the file and distribute from my server. In windows EXE's the tracking works fine. But in DMG's for MAC's The tracking seems to be lost after the the file is moved to another computer. Example : I dowload the file from affiliate servers, example: setup_1237277.dmg and host it to my server for people to download. As soon as i do that it seems that the tracking is lost. The installs dont count towards my account and the file name is the same.

I am really lost and as i have no clue about Mac's i cant think what could be wrong. Any help?

Speak to the Affiliate Network. Could be something to do with the filename when moved ie the extension is included in the filename (.dmg) or something.
They must have had this before. if they can't answer, then they 'probably' aren't the network to be working with long term.