Help! Desperate - Installation problems

Hi Guys
So I downloaded the latest version of shotcut as it became available, since then mega problems.
It was suggested that I uninstall and then re-install, which I did, but…
Now absolutely nothing. The program installer downloads but that’s all. I get no shotcut whatsoever.
I am on Windows 10 64 bit laptop. No idea what a github or the other one is, but tried both versions. Both installed with the same result, nothing! When installing my laptop will not allow me to check the Install program files box, it is grey and uncheckable. Is this the problem, if so how to overcome?

It says you can install an earlier version, but I can’t cant find the button.

I have successfully edited 5 videos on shotcut, no problems, it is only since this latest download.

Looks like I’ll have to investigate another open source. I am not earning any money whatsoever from these videos, a hobby, and on V. limited income, so cannot afford to pay.
I’ll wait a couple of days for replies and then give up, frustrated and disappointed.

Can the Shotcut installer be blocked by antivirus on your PC?
Did you try to download the portable version (.zip)?
The portable version does not need installation, just unzip the .zip file and then run Shotcut.exe which is in the unzipped folder.
Can you take a screenshot where it appears that you cannot check the install box for Shotcut files?

Did you install with admin rights? Seems to me some protection problems -wiered.
Would uninstall all and stick to the older version if this worked for you. But surely would be better to solve the problem.

Make sure you’re downloading Shotcut from here: https://shotcut.org/download/
GitHub & FossHub are websites where the installer files are stored on.

Which box is grey and uncheckable?
Can you provide a screenshot?
shotcut-win64-200927_2020-10-14_13-36-23
shotcut-win64-200927_2020-10-14_13-35-36
If you can make to this screen, have you tried checking “Remove Shotcut Settings From Registry”?
shotcut-win64-200927_2020-10-14_13-36-02

This is normal because the installer always installs the program. It should be already checked.

I get no shotcut whatsoever.

How do you know? What are you looking for, and where but could not find? The installer does not run Shotcut; it only installs it. Maybe you do not know how to start Shotcut after it was installed: