I'm not familiar with Corel VideoStydio Pro X8 and don't know which version it requires, or if it attempts to install a version of Flash Player (some programs do that). The latter appears to be the case, based on your post.
You'll first need to uninstall the current installed version using the standalone installer posted at Uninstall Flash Player for Windows. Previous versions of Flash Player are posted at Archived Adobe Flash Player versions. Locate the link for the version you need and download that version. A compressed zip file will download. After uncompressing the file, go to the folder named with just the version number (ignore the folder named Version_debugger, this is for developers to debug their code). I believe Corel VideoSudio uses the Flash Player ActiveX Control so you'll want to use the file that has 'activex' in the file name.
Also, please understand that reverting to a previous version of Flash Player puts you at significant risk for malware infection. If you're using the computer for anything confidential (banking, healthcare, etc) with it, I'd strongly recommend that you reconsider this approach and instead find a current or alternate video tool that doesn't have this dependency.
I tried it but for some reason did not succeed.
Ifound out that there is a correction patch for the Corel program, and used it.