But guys you miss the point - errors ARE NOT relevant if a clean way exists to do this.
I'm afraid that is the point - there are a multitude of very clean, very well-documented approaches to setting up a Linux C/C++ development environment in general, and there are many of us that do the whole process from scratch weekly if not daily. We know the build process works (for some in the very environment you seem to be using), so there has to have been either a missing component or a user error. I am not an OpenWRT dev (even though I've been around the Linux programming block a time or five), but thepeople most definitely is, and it would behoove you to listen to what they say about the build process.
Meaning 1-2-3 and it works.
Therein lies the problem - you are insisting on somebody spoon-feeding you baby steps when you're trying to venture into an area where you must understand at least the basic concepts and cannot blindly fumble around. The OWRT devs have done a fantastic job of streamlining the build process and making it nearly self-sufficient, which comes back to the issue of, "show us your error and we'll fix your problem."
Here's the thing: I may be alone in voicing this, but I detest and refuse to author or support HOWTOs. The reason behind this is that they take too much post-authorship work to maintain as a relevant work and are far too brittle - if someone wants or needs to deviate from the steps outlined, they get hopelessly lost. Whether they agree or not, users need concepts, not steps. [insert aphorism about teaching to fish] I have yet to encounter a series of steps to do anything that are absolutely fool-proof and guarantee 100% success for all users. Yes, I'm a cynical engineer and know just about everyone does some kind of deviation from given steps.
If you are really up for tackling installing Gentoo, the only additional software you need to install is subversion; everything else the OWRT buildroot needs is already there due to Gentoo's compile-from-source approach. However, it is developer-friendly, not user-friendly. A more user-friendly flavor (Fedora, Ubuntu, etc.) typically need some extras that often come in the form of a "development" package group or the like; if you just took the shotgun "install everything" approach, you probably have what you need.