Porting particle FX from a newer engine/DMXConvert?

So right now I’m trying to port a particle effect from Insurgency (which is on the 2013/CSGO branch of Source) backwards into GMod, which afaik is on a slightly earlier engine branch.
The particle effects don’t use anything weird, so the pcf itself should be compatible. The problem comes when I load it ingame - when opening it in the Particle Editor, it crashes back to the main menu with console messages stating “Unserialize: Unable to run conversion process ‘dmxconvert’ [my pcf]”, “temp_conversion_file.dmx”, and finally “Fatal error loading [my pcf]”. The particle doesn’t appear in either the editor or in gameplay.

I’m only a few days new to particles, but I can guess that there might be compatibility problems with DMXConvert when trying to load a particle effect from a newer engine.
Apparently just copy-pasting a PCF from another game and editing GMod’s particle manifest doesn’t cut it. I’m not sure what’s going on, but 4+ hours of googling only brought back SFM & modelling questions (unanswered), that and there’s barely any documentation for DMX/custom particles/etc so this is my last resort.

I’m at a loss, and I do know this is possible, so if anyone has experience porting PCFs from Portal 2/CSGO/etc back into GMod, or even just creating custom particles, I’d really appreciate your advice/guesses. Thank you!