Short version: You need to mount your iso and a way to initiate it.
Long version:
It doesn't matter what version of Kodi you use when launching an external player. I use v.18.1 now. Without getting into another lengthy explanation, you're better off using a packed iso vs unpacked folder structure. Iso extensions need some handling to 'unpack' them from the container so they are readable. This is called 'mounting'. Some players have an internal mounting program built into them like PowerDVD, DVDFab Media Player, Kodi internal VideoPlayer, and Windows itself. MPC-HC/BE do not have an internal mounting program so one must be provided for them otherwise they remain packed and are unreadable. I use Virtual Clone Drive (VCD)
http://www.slysoft.com/en/virtual-clonedrive.html and assign a drive letter for this virtual BDMV drive just as if it was an actual dedicated hardware player you placed your physical disc into.
A playercorefactory.xml (PCF.xml) is not a mounting program. It just interrupts normal Kodi operations and directs to alternate ones mainly providing an avenue to call external players based on locations you provide and rules to distinguish which and when. I use it a couple different ways:
For players with their own internal iso mounting program built in, I simply provide the location of the these players .exe's start files and they handle the rest providing full menus of a 1:1 rip.
For players without their own mounting program, I provide VCD to do it for them. To run this mounting program, the PCF.xml is not enough so I provide a .bat to launch it with the chosen player. Even though they mount and become readable, all I have accomplished is to unpack them from their iso container and reveal the folders and files called 'structure'. Just because everything is now accessible doesn't mean the player(s) know what to do with all these folders and files. So, unlike PowerDVD or Fab players, which do know exactly what to do with all these files and folders displaying them in all their glory with menus, extras and such... players such as MPC-HC/BE, Kodi VideoPlayer, etc., seek the largest file and only play that portion of the rip which is usually only the main movie. This is all they are designed for and do not share the same intelligent deciphering of the structure other players do.
So, for example, to launch an hdr.iso with MPC-HC and all the other goodies like madVR and LAV Filters, it works like this 'basically':
You press enter or play on the title in Kodi.
Kodi notices you have a PCF.xml and redirects to the commands in it bypassing its own internal player and obeying the PCF.xml.
You know your iso needs to be mounted or nothing is going to happen so you direct your PCF.xml to call a .bat associated for MPC-HC under this condition based on rules you created in the PCF.xml for hdr.iso titles.
Within the .bat are criteria: If the file is an iso, mount it using the VCD program and once it's mounted, assign a drive letter because Windows requires a drive letter for everything to identify it. Assign drive letter 'A' because I am not presently using it for anything else and it's available.
The .bat goes on to command - after this mounting and drive letter assignment is completed, open another program - MPC-HC.
Once MPC-HC has started, source it to play the mounted structure in drive letter 'A' and let it take over from there.
MPC-HC proceeds to read the metadata in drive 'A' and determines (per its own settings) to also call upon LAV Filters and madVR to join the party.
LAV Filters and madVR make their own adjustments based on the settings you provided them.
Your GPU drivers are also informed what decoding is needed from them including assistance from LAV and madVR and finally handed to your display.
Your display obeys how to render and makes final adjustments and at last produces a picture.
All of this is accomplished in a few seconds and before you know it, you're watching your iso exactly as you set it up to do.
When finished, everything you called up closes and your iso dismounts leaving Kodi in focus ready for its next assignment. No trace of what you did exists and will have a fresh start the next time you press play on a title in your Kodi library.
