It wouldn't take me very long to do the pipe from scratch. Lets time it. its exactly 9:00am here.
edit: ps I like the Maprookie site changes! (the icons and header graphics look nice)
Just for that i'm going to answer you're questions in excruciating detail.
Q1: On the menu bar, go to Customize > Customize User Interface...
A bunch of tabs will appear. Click the colors tab. Click the first drop down labeled Elements, and choose Grid. You can then set the Color and intensity, or invert them to look like hammer.
Q2: I don't know either. I'm guessing object space is the stuff thats within an object, like elements and faces, and world space is outside the object and includes everything as a whole. Like World Brushes and Entity brushes in hammer. Although I could be wrong. Please link to a tutorial that mentions this so I may get some context out of it.
Q3: Not as far as I know. Although you can customize your keys if it makes it easier for you.
EDIT: Not done yet, but i found out whats wrong your model from before because it just happened to me. It has to do with the "Unfolding Mapping..." tool. If that ever happens, remap the part with a different method, either Flatten Mapping or a projection like planar, or cylindrical or whatever applies.
As far as my timing, i got distracted. Had to watch "Marine throws puppy off cliff"
and the madatory Ironman trailers.
EDIT: i took minute an 1 hour and 4 minutes without pelt mapping.
Pelt mapping would take 15 minutes.