Copied from the comments:

You need to opt-in to the beta. Right click on majesty in steam, click on properties, and select the betas" tab. Then select the beta from the dropdown menu.

thank you!
needed that information :)

already opt-in to the beta.
but all the mods except maps don`t work.
why?

I don't know anything about map downloads other than they should show up in Downloaded Quests. When you click Play Game, it's the icon located at the top left corner.

Thanks.I found it.
The problem was only that in the 800*600 display mode can`t see the change mods button.

my properties tab doesnt seem to have a beta tab...

I solve same problem yesterday: copy download files to the "mods" folder (manually). Means that you need to know where all steam mods download to and where (which folder) is your game was installed to. Beta option enabled, mods copied by your "hand" and it`s works! Any other advice didn`t help.

Thanks Victod, you're the best. It helped.

I'm also having an issue running this and have tried about everything and would like to see if there are anymore suggestions.

I have
-Subcribed to the mod of course, and also unsubscribed and subscribed again in between attempts.
-Gone to "properties" and the only thing availble is the beta of multiplayer. I've toggled this on and off just in case.
-Looked in the mod window in the game anyways, just in case.
-Moved the files for the mod from downloads to content, where other Majesty mods were.
-Removed all mods and uninstalled and reinstalled the game

and I've restarted steam between each of these attempts and it never even shows up in properties >betas.

any ideas?

Is it just my mod that won't show up, or any mod whatsoever?

So, weirdest thing... I just added a bunch of other mods to see if all others would work except this one, and when I went to the mod window in game, your mod was there in the list with the others. I didn't have the option to add it to beta in properties still, but it's there now.

When I just had a couple modded levels, and even after I got rid of everything and only had added yours, there was nothing.

But! It's there now so *shrug*