That Playlist Loader Player is installed thru Kodi , from that superRepo (or other repo).
You got that Player from the SuperRepo didn't you ?
If so then it should be found in your Video Addons area on the Kodi Bar
It is the m3u Playlist itself, that stays on the uSB device.
An m3u playlist, is simply a gathering of web address' with each specific to one channel. When you change the channel on your remote, the player gets the web address from that Playlist. That is really the only function the Playlist does, is to supply the addresses.
With some Players, you can enter the actual address that the complete Playlist came from (ie the Generic M3U file address from Rocket, the one you generated when you deleted your MAC and choose a Playlist). Then you do not need that Playlist in hand,the Player will connect to that address you generated.
That Playlist Loader will do that, I never tried that way with it thou. But it asks you upon start up weather you wanna connect thru URL or thru Local... with Local being the USB and Playlist in hand method.
It also has a place to enter an EPG URL , and that is what kens was mentioning.
I would retry using the PVR IPTV Simple Client which kens also mentions.
Be careful on which is the app thou, there are many apps with similar name... PVR Stalker, Simple IPTV, Simple TV, Simple TV Client, IPTV STB and the list goes on.
Ensure that it is ..... PVR IPTV Simple Client.
That Perfect Player kens mentioned may be worth trying to get installed too.
That one to get from Google Store.. you would need a web browser installed thru Kodi on the T6 to access google store, then the store installs the Perfect Player application direct onto your Kodi for you.
So you would need to get a Browser installed onto your T6 and Kodi. That prolly would need to be done thru an apk load or thru a Kodi repo that has a browser included. Or find that Player included in a Kodi Repo or addon (zip) form (google search may help with that)
The T6 is not the best when it comes to running apps or installs and such things with its older version Android Operating System and its older version Kodi.
Is generally why I prefer the apk download method on the T6 as appossed to the Browsers and things.
If the apk version of any app or Player can be found, then it is just a simple process to load that apk file onto the T6... (no messing around with Kodi or Browsers or errors or a confused T6)..... well lets not count my recent mishap loading an apk... lol ... I had a few corrupt file transfers
Some things are hard to find other then thru Google Playstore thou.
Perfect Player can be found online in apk form
That git hub link kens supplied will give you more then just channel identifier names, as you only see now thru that Player.