Tridus,
I think that ultimately the issue comes down to this: Stardock decided to put LAN support (i.e. Custom Servers) on the list for post-release. They did that so that they could finish other things that they deemed more important.
You feel that any MP game should not only have internet games avaialble but also complete modding and Lan Support at release time or it is unfinished from a MP perspective.
I disagree that for the game to be complete it needs those features. That you took Brad's comments as a promise is unfortunate, and is probably the reason most developers don't comment on forums. Just because Brad said he wanted those features and they were initially planned doesn't mean that they were guaranteed to be in. The same can be said for continuous turns, just because they were said to be in, and then were taken out doesn't mean that I am not getting what was promised.
First of all, thanks for a very calm and well written reply. 
Speaking personally, the modding thing bothers me more then the LAN thing. The LAN thing took over and while I'm not happy about it, it's no different then Starcraft 2 and I live with it there. But the modding thing? My intention for the game is to play both SP and MP with a friend who also bought the game, and do some modding (in particular Wizards towers ala AoW 2, so a sovereign could stay and home and cast).
From the stuff I've linked, I think it's easy to understand why I expected to be able to play that mod MP. In release, I won't be able to. Nowhere until this week was it stated that mods wouldn't work in MP at release (or that there was no LAN support).
Bottomline: Stardock didn't intentionally mislead you. They want to provide custom servers still, they didn't make it for the release version. LAN play with a single copy is not an option in this game, and is not the best business decision anyway.
I don't think I was misled, I think the deadline happened. But it does beg the question of if modding is considered a core part of the game (and it's advertised as one), is the game really ready for release if mods don't work in MP? That's an opinion point, but IMO, no. LAN play happens to come with it, because the two problems share the same solution (custom servers).
Which is a problem, since if the game isn't actually ready for release due to missing that feature but it's coming out anyway, Stardock just broke their own Gamer's Bill of Rights.
As for the LAN with a single copy thing, that was never promised for Elemental. But it was something Stardock did in previous games like Sins (2 people for one copy on LAN), and it was a great way to introduce a friend to the game. It's a shame they didn't continue it. There's been a trend away from that sort of thing, I was actually surprised to find guest passes in my copy of Starcraft 2 that are fully functional.
The point of the thread is: "Hey you can get the game set up on your internal network that is connected to the internet before your friends come over to play. Here's how you do it... BTW you will each need a unique serial to play on the Stardock servers you are connecting to." The point was never to say this is how you set up a LAN only game or if/when the game will support 15 players playing 1 copy of the game on a non-connect LAN with 15 mods running on a custom server.
Unfortunately this is also the thread where we found out about the lack of LAN support and the MP mods issue, so the reaction is here. Another commenter mentioned expectations, and I think that's the problem. Blizzard's lack of LAN support wasn't a surprise, they told people months in advance. We just found out about it, in this thread. Had they said this feature wouldn't make release 2 months ago? We're probably not having this conversation.
I respect that you are disappointed, and I don't have any problem with you posting to ask for more LAN support, but I do have a problem with the feeling of entitlement people have. You pre-ordered a game that could have changed wildly before release, it could be a FPS and you took the risk by pre-ordering that you were going to get whatever they produced whether you liked it or not. If you felt that a certain feature was critical to your happiness then you shouldn't have ordered until after the fact. That you feel mislead doesn't mean that you were.
No particular argument there, I've learned my lesson. (Actually as a rule I don't pre-order games and usually only buy after a demo. Given my good experiences with Stardock in the past, this time was an exception. I'll go back to sticking to that rule in the future.)