Hi there !
I've got the same kind of problem, I downloaded from within 7th heaven the Tsunamods Arranged Soundtrack, the Symphonic Remasters, the EDM one ... None of them worked. I've tweaked eveything, I've set VGMStream in the advanced tab, activated the mod separately, removed the mods, then reinstalled it ... When I launch the game, only the general midi soundtrack is played. All the other graphic/textures mods seem to work.
I've tried different version of 7th heaven (the 2.3.1.97 one and the 2.3.1.0), it does not change anything.
Any advice ?