Yep.
So do I, I'm working on my module right now but running into some troubles which (unfortunately) noone on these forums seemed to encounter so far, so I think that might slow me down...

I think I have a small story/analysis to tell.

[bit OT]
I work mainly with the Unreal Engine and having started with Unreal Engine 1 and having witnessed the Unreal Editor 1, these were also quite some unpolished tools.
To quote the packaging:
"Includes Unsupported* Beta Version of the Unreal Level Editor
[bunch of text]
* No manual. No technical support. And it might even have some bugs. But we made the game with it. :)"
However, oddly, I struggled less with that one and managed to learn it fast and get a better idea of the possibilities (and bugs) than with the Divinity Engine and the UEd1 was also beta and original developer tool - and crashprone, albeit (which is sad) less than most modern beta and even final mapeditors nowadays. We can be happy that the Divinity Engine doesn't fall into the "crashprone and highly annoying" category at all. :P
I assume that I had less troubles with the UEd because it is an editor for an engine that is rather optimized for shooters and less for story-driven games with lots of dialogue, so it is rather "artist friendly". Larian's tools and the game however also require some coding if one wants to make something which isn't just "walk and kill stuff", aka something on par with the game/genre standards, so one has to invest more time into it.
Then again, the days of the Unreal Engine 1 (for those who don't know it, ca. 1998-2002/3) were entirely different times where the average hill consisted of max 6 polys and textures (plain image files and no combinations of such as materials nowadays) had a size of 128x128p, with no heightmaps and a pretty rigid level design that didn't allow for open world but just for "level after level" linear-setup.
Things changed a lot since and the modern engine versions are harder to master due to a wider amount of possibilities - or maybe I'm just getting old. lol
I'm actually surprised that the editor we got from Larian got this many possibilities. Usually, companies release some stripped down tools for the average user to just open up and paint something which in the end gets restricted results compared to the real game (I won't bash any game/engine/company here out of respect).
Basically a pure map-editor with barely any features. On top of that, these often seem rushed, are bugged, pretty annoying in usage because they're just "too userfriendly" (trying to think for the user and re-aligning static meshes without a setting to disable that is highly annoying imho because it forces you to mainstream usage of content) and on top of that they crash every 5 minutes or have autosaves that are so intrusive that they're annoying.
I think that it might be the amount of possibilities of the Divinity Engine compared to other mainstream editors for other games and simply the lack of documentation which makes it harder to master but at least for me the knowledge about the possibilities motivates me to keep at it because I know I can make something acceptable and enjoyable (unlike with other software...).
The only other rpg-mapping tool that comes close to the Divinity Engine would be the NWN1 Aurora Editor (for those who don't know it: NWN was released in 2002 and so was its editor iIrc), which imo got even beaten regarding possibilities since Larian's tools have no grid limitations and a proper house editor - not to mention the heightmap support. The lack thereof in the Aurora tools is something which I blame on limitations back then.
This is a big + for the tools we got here. It is true though that some stuff was simply easier to achieve with the Aurora Editor (as I have seen others point out), e.g. giving an NPC inventory or changing his/her stats or things alike.
However, once I understood something regarding the Divinity Engine, I noticed that the thoughts behind "why" were quite simple compared to other stuff I worked with.
It wouldn't be hard to master if not for the lack of information, but I guess we need some patience. Larian has had enough to do with the game and deserves a break before continuing explaining the editor in detail.
By the way, the programmers are surely not at fault at all, they should rather be proud, read this and take my post as a big compliment because, honestly, I was never confronted with such a powerful editor for an RPG game so far.
[/bit OT]
Kolto-Cola: The fact that Larian managed to create such a good game with the given tools is that they got introduced to it from the very beginning of development. Don't forget, they even mentioned those are their inhouse-tools. They had the time to learn it and the tool creators could actively tell them "this does this and this does that, beware about this tool, I didn't test it yet and it might be crashprone or bug around, so make backups, etc, etc", additionally, game development is split into categories: modellers, mappers, story writers, programmers, etc.. As you might have noticed in the twitch-stream "modding tutorial", a single person didn't know the entire editor/tools themselves, just the area they usually work with and since they had no programmer at hand, they couldn't exactly show how to create a storyline (unfortunately).
Add to this that (thanks to the community and kickstarter backers) there were a lot of people who could test the campaign and give proper feedback so they could polish the game.
Either way, to summarize it for the tl;dr-ers:The tools are not bad, on the contrary, compared to most other editors for games they are very powerful and don't suck. All they really need is a documentation/more tutorials. :P