You can get rid of the workingbox simply by clicking the icons on the top of the assembly screen, I usually just leave the ground plane on as a single reference point, otherwise it's a bit of an illusion because you can scale up as much as you like just about. Johannes did an awesome job on that tut and it would be cool to see it updated. As for assembly itself in carrara, the more you can model "in place" the better off you are and for architectural stuff well ya, it would be nice to have something similar to "snap to" bounding box to bounding box or something so you could snap a car to a road or snap a dish to a table top etc... And then nudge it with the universal manipulator or something... The Universal manipulator supposedly coming out in C6 will be cool, but it may also be behind to some degree by the time it gets there. Scene management tools will be welcome because it's so easy to build a ton of models in hex and then have to place them with the somewhat dated move tool and collision detection (if you even bother to use it).