So Player App Not Installed. The logic being it's trying to direct you away from random.apk installs not from the appstore. You should be doubly sure of the source from where you download an app, check its extension name, and make an effort not to install contained files.
First time the app runs the user is asked to find the folder and click on one of the files. Click continue or provide administrator credentials if prompted. I have provided all the links to video tutorials, the review, and so on (see above) to help you learn more.
The playlist is saved to tinydb.
Once the so player app is installed on your compatible device, the next step needed is the iptv service to activate the app and deliver all the streaming content. Flash player is a browser plugin, it's not a standalone app that you open by itself. Just scroll at the bottom and you will see the vlc media player icon appears there just hover to it and press the select button to launch it. After each step, restart your phone to see if it fixed the issue.