So updated to build 90, then I copied the track into packages folder (along with other mod updates). I could update the mods in mod manager but the new track did not appear in the mod list, so I cannot install it into the game. What seems to be the officer, problem?
Perhaps you didnt uncheck the "Show mods only" option in the Mod Manager? (it is in the Options menu, upper left side of Mod Manager). When "Show mods only" is unchecked you can see the full list of the components and, i guess, the track is just a component, not a mod. Still new components require a installation, so you will have to install the track!