It was all going great guns until this bit:

"Now the middle section of your corridor is done, its time to work on the entrance sections. Hide everything on the map except for one of the end sections and the middle of the corridor you have just made. For this example we will make the end bits serve the purpose of neatening up the brushwork of the corridor for easy transition into the rooms at the ends. That does not mean to say that they need to be rectangular in shape.

Use your clip tool to split the end section?s wall into 3 bits, and the ceiling into 3 also. Now change your grid size to 4, and using the vertex tool create the shape shown below. Note that the floor is not changing, so you can use that as reference to ensure everything is lined up correctly. Once you have one wall made, you can clone it and flip it rather than going through the process of making the second wall."

I guess not having any dimesions to work with just threw me
I'll keep hacking away at it though. Maybe after reading the same bit a dozen times I'll realise something I didn't last time. EDIT: Hey I can't seem to make the brushes line up without altering the shape of them

You forgot this one Candyman.

i make a cube, and carve out the middle with a sphere.

works ever time.

edit: cept that one time.. when i was also dividing by 0. that was quite a day.

O.M.G. man this tutorial is the greatest!!! TOTALLY AWESOME DUDE!!! I done it I actually done it!!! JUST DON'T MENTION INTERSECTING BRUSHES HERE AND THERE! O.M.G., O.M.G., O.M.G. I want to give everyone a big hug I can only begin to fathom the possibilities!!! I have finally come of age! (At least I think I have, I dunno how to tell for certain) Basically, I was worrying about stuff that was going to be covered later in the tutorial so there was no need to line up everything at a certain stage if you know what I mean...he used a method that I always forget about I'ma probably follow that tutorial again twice just to get everything exact.