Well you can. You can also download the Mod here:
http://grimrock.nexusmods.com/mods/239

But this is "just" a remake of the entire game using the editor! If you are a modder this might be of interest to you because Komag commented everything on how he could remade the game with just the editor.

Edit: Uhh Komag remade the Mod and added(just like your link said) a ton of new changes so that this is more like Zelda the Masterquest - same game but with some changes. Well im downloading it right now. Fear not to register at grimrock nexusmods - you will not receive spam or anything like that.

I just got the game and have only made my party, I haven't really started yet.

So should I play with this mod or just play the original game?

I'd love to, but it sucks that supporting GoG is apparently going to cost more money if you want these add-ons, as the they require a paid subscription to download it. If I'd bought it through steam, I could download it for free. Live and learn I guess. Be buying games that are on both services through steam in the future.

What paid subscription? i think you missread something. It does not cost money to register at grimrock nexus! It just sucks that you have to register in order to download....but it DOES NOT COST MONEY! The Masterquest is harder and some puzzles are different. I recommend playing the original and then the MasterQuest. But it is your choice. Since the story is the same you can just try it out :)

Thanks for the clarification about the Nexus being free - I thought it cost money to register as well.

I wish we could use nexusmods without the registration. i bet more people would use it to download mods ... but then again...i dont want to use steam and thus this is the only source for mods(and there are great ones like eye of the dragon, the one room dungeon, the mine of malan vael, the tomb of zarthos, the wine merchants basements and many more).

Here is also a statement from the hoster of nexusmods:
http://www.grimrock.net/forum/viewtopic.php?f=14&t=3024

Nexus is a GREAT website! It's definitely worth the 0 cost of getting an account there. You can pay to get faster download speeds but you don't have to. You can donate to the folks who make mods, too, but again you don't have to.

Good thing I found this thread about the Master Quest. I just imported my party from level 5 and started playing the modded version instead of the original!
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