Dolmen is a classic format stage, so it goes to \Maps. What is your current setup as in do you have RSRBR/RBRTM/copy of vanilla or something else?
RBRTM would be ideal platform (I assume you don't have it), new stages often get added to online events so quickly - with user-friendly installers - that you may not even have to learn what I'm about to tell you. You'd have the separate menu and you wouldn't be replacing the original stages. Like this:
https://4.bp.blogspot.com/-AB4AQqt9...IS9oIZqkk-4bTNNbT9qyQCLcB/s1600/shakedown.png
RSRBR has its own testing module for classic format stages and while it's better than nothing, it's not ideal by any means. Basically, to use Dolmen as an example, it as a gravel stage would replace an original RBR gravel stage, and if you're lucky, it would actually work on this predetermined slot (this is not a certainty). And because this workaround dismisses the stage's own tracksettings, what you'll see may not be at all how the stage maker intended it.
But let's wrap this up already. I expect tracks.txt to have these lines:
[Map755]
TrackName = "Maps\track-755"
Particles = "Maps\ps_british"
StageName = "Dolmen"
Surface = 1
Length = 13.38
SplashScreen="Textures\Splash\DolmenSplashScreen.dds"
You just copy these lines to the end of your \Maps\Tracks.ini. And tracksetting.txt has another set of lines that you copy to the end of your \Maps\TrackSettings.ini. Simple as that. The pack obviously has that loading screen dds too which - if you had RBRTM that supports custom loading screens - would go to \Textures\Splash.
If you wanted to temporarily replace an original stage, you'd just open Tracks.ini, edit [Map755] to something like [Map20] (to replace Harwood Forest), and scroll up to the original [Map20] entry and change it to [Map]. If the game crashes, try another slot. Use this as a guide:
https://www.dropbox.com/s/idpf9o751n1oto4/RBR-stage-numbers.txt?dl=0
Good luck.
