Hi, I wanted to give an update over what has happened so far.
So first this "TPLS" or PS1 Soundtrack extension has been integrated into Rayman Control Panel by RayCarrot too, see here:
https://raymanpc.com/forum/viewtopic.php?t=25761 . The way it works there is by using a custom DOSBox with his derived code of my original TPLS basically baked into it. That said custom DOSBox with its new code has been provided by PluMGMK, see
here .
Rayman Plus originally had the TPLS module working as a single entity, by hooking into Windows' ReadProcess API call to detect the game data. Afaik that idea however could only work in Windows, so having a direct native port into another OS' can't be done easily with that premise.
After a while, I myself started making a transition into Linux. During that time I've decided to port the original Code into something more modular. It was originally written (and basically was hardcoded with Rayman Plus) in C#. I've since ported the original into C++ and published the code
here.
I took Plum's original idea and had also baked my entire original code into the Linux version of DOSBox. This is available through Lutris now, if you wanna install the GOG release of Rayman Forever.
So in short: There was a derived version of TPLS baked in DOSBox itself which is available through RCP for Windows. I've open-sourced a reimplemention of TPLS, and also baked it into DOSBox and made it available through Lutris for Linux based OS'.