The Grid is always there, with the option of having it visible/invisible.
Creating a big Scene is a combination of Grid size & spacing & different Camera angles. But you need to have all Props on the Grid. Otherwise it would be impossible to place them correctly in their relative positions.
If you set the Grid at the bottom of the Viewport, with a combination of Orbit & Zoom (Like my Screenshot to be added) in Preview Camera, temporarily selecting that as Camera 1 & then Locking it, you can gradually build-up your Scene in Preview Camera Mode, switching between Camera 1 to check/re-check the desired result.
I've Selected 200 for Grid Size & Spacing. The Preview Camera Angle saved as Camera 1, is pretty good for most Scene setting. To test; Drop the Deckhouse Prop with Snap To Grid Selected & any Character, into the Scene.
Scaling-down 3D Scenes, Terrains & building Props to 50%, would reduce the overall size. However all other non-building Props Characters would need to be Scaled-down by whatever % you use for Buildings.
A complete Medieval Village from the Medieval Village pack would be a good example.
The best Tutorial I've seen & learned by heart & now do without thinking about it, is Stuckon3D's paid-for Introduction to iClone4 Class, where he lays-out some of the Props from the Suburbs in Winter Pack. You need to scroll through the Video to approx the last 30 minutes, maybe longer.
Ther'e shorter Free 3 separate Tuts of his, where he builds a castle. Part 1 Free intriduction Cless to iClone4 has the Grid, I think.
2nd 1 is in the Wiki. 1st, possibly not, since it's not free.
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New Pinhead Website & Project to be announced in September 2015
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