Guys, they are changing compilers because MINGW's C compiler is getting weird and scary in places, as well as being less optimized for Windows in general. They've also likely been on the compiler they used at the start of development, which was 2 years ago IIRC. It's pretty necessary, and honestly not that big of a deal.
It's not changing the house, it's more like changing the locks.
More than that, your assumptions on hemmingjay's words are rather impressive. Ranging from assuming they have multiple codebases(Something that a large variety of games do/did have.) To those code bases being utterly unable to work together.
What they are doing in programming terms is object oriented design in it's purest form. As far as I can tell, they have all the feature sets there, they just are trying to make them interact. Depending on their setup and the tools they have, this ranges from mildly tedious, to "Oh I'm done."
Essentially they have the code for the GUI set up, and the code for the crafting set up, so that neither requires the other to run, which is excellent use of object oriented programming. Now what they need to do is have the code interact with each other, so the GUI can display crafting, crafting can plug stuff into the gui, etc. Given their previous progress and fast implementation, this game should be out before thanksgiving at the latest.
The other option is that Hemmingjay completely misunderstood his "contact," and they are talking about the standard issue of gameplay in games like this. Which is that everything feels mostly disconnected, and making all these systems work together could be difficult.
How to make it so that the player has incentive to compose ballads using their music system. Or complete quests, when the quests probably don't reward you with anything of note, because by the very nature of games like this everything is craftable. How to make it so that combat is rewarding while still being in line with all of the other features. These are all rhetorical and I'm not expecting answers to them, they are mostly examples of the issues that come up in game design. Games like this are not easy, because they have no real goal, other than what you set for yourself. They have a good core concept and that's that the game is a metroidvania styled game, with crafting and space travel. But how do they communicate that with the players. How do you make it so that all aspects of the game are rewarding. Minecraft's is easy because you've got no real goal, you just have blocks and infinite possibilities. The moment you introduce a goal or a story into the game you run into issues. How do you make the faffing about the genre relies on compensate for the need for tensity. Or to say it another simpler way, how do you make the narrative compensate for the poster collecting, or the going around to places erecting giant statues of your penis so the masses may be educated of it's glory? These are legitimate concerns that come up in games like this, where you have ample time to just sit around and think, "Who am I and why am I doing this?"
That right there is one of the main reasons why the elder scrolls games have felt inconsistent to me since Morrowind. In Daggerfall you needed political capital, you needed a reputation, to even think about succeeding at preventing the rebellion. In Morrowind the danger was much more present, but was again in the stages of building up forces, taking on an Empire and then the Gods themselves takes time after all. After that though it's a case of, " TAKE THIS AND USE IT TO CLOSE SHUT THE MAWS OF OBLIVION." "Nah I think I'll just faff about. Stop the rebellion in the mages, guild, destroy a rival drug trading fighters guild. See the Dark Brotherhood completely collapse. Restore the position of the COUNT OF MONTE BRAVIL. You know that kinda stuff." There's too much going on, too fast, and it just all loses meaning. Especially when you have that crucial time to go "Who am I, what am I doing and why." The game loses all sorts of meaning, if you have anticipation, a strong plot, a fast guiding strand of main plot, and then you lose the players completely by just letting them do whatever they want.
Imagine how tense Oblivion would have been if they kept your focus on the main plot. Instead of leading you around with dozens of side quests and ancilliary plots all while, "QUICKLY YOU MUST SHUT CLOSE THE JAWS OF OBLIVION"
That was a tangent but I really felt I couldn't explain it well without a hyperbolic explanation like that. Oblivion is probably one of the worse examples I could have used. But it does bring up a good point. Sandbox games don't work unless there's a reason behind all the faffing about, if there's any sense of urgency at all.