Flash Content Flickering

After recent update, Flash content flickers in both Chrome and Firefox. There are no videos and this does not apply to any videos.I can't figure out how to fix both the flickering and installtion problems.

Operating system version: Windows 7 Home Premium SP1

Web browser and version: Google Chrome Version 49.0.2623.87 m and FireFox 44.0.2

Flash Player version: none - I removed it (version 21.0.0.182 both ActiveX and NPAPI versions separately), but Flash still plays in Chrome and FireFox

Explain your problem in step-by-step detail if possible:

Updated Flash to latest version 21.0.0.182

Flickering screens appeared in both browsers (not videos)

Uninstalled Flash in order to install previous version

Went to download previous version of Flash, non-developer version

Cannot determine which version is immediately prior to 21.0.0.182

Downloaded fp_20.0.0.286.zip

Extracted files

Error:Confirm Encryption Loss

"A problem is preenting this folder from being encrypted."

fp_20_0_r0_286

Yes Skip Cancel

Selected "Yes"

Error:Confirm Encryption Loss

"A problem is preenting this folder from being encrypted."

fp_20_0_r0_286debug

Yes Skip Cancel

Selected "Yes"

Did not know which file to run in order to install

Ran installer file: flashplayer20_0r0_286_win.msi

"Installing Adobe Flash Player 20 NPAPI"

No error

Ran installer file: flashplayer20_0r0_286_winax.msi

"Installing Adobe Flash Player 20 ActiveX

Error 1722 There is a problem with this Windows Installer package..."

"The wizard was interrupted before Adobe Flash Player 20 ActiveX could be completed."

I can neither install an earlier version, nor stop the flickering.

A direct link to a web page that demonstrates the problem:

password protected page: https://newconnect.mheducation.com/flow/connect.html