Reinstall programme without msi

I want/need to do a clean reinstall of Windows 7 (tried 10 and it just isn't me). I currently have a very useful and valuable application installed for which I no longer have the installer package. It is legal and I do have the key. But I will not be able to reinstall this programme once I've done the clean OS reinstall. The software house no longer supports this programme and I have not been able to find another copy of it anywhere on the internet.

I have found this registry key which presumably relates to the programme in question:
HKEY_USERS\S-1-5-21-3881858240-96957817-3944641873-1001\Software\Collins
But it only has a load of user settings inside.

I was hoping that if I saved this registry entry and the entire folder structure and file contents for this programme that I could just neatly put everything back in place after the reinstall of OS. But this is probably just wishful thinking.

Could someone suggest what measures I should take to get my programme safely over to the new install of OS.

Thanks

Program name is kinda essential . :)

Hello. Yes I have looked in Downloads and just about everywhere else, even under the bed. And the Help just directs me to a useless Collins site. The programme is Collings Concise English-French Dictionary. I have since managed, after much research, to find a new Collins enquiry site and have contacted them but still await a reply. Am I right to assume that without this installer there is no way of salvaging the programme for putting back after the clean OS install?