Yes, exactly right!

I think there should be a hotkey and a shortcut bar icon that when pressed puts the player into ghost building mode. In this mode, placing ghost entities rather than real entities is the default behaviour when you left-click. Shift + left-click would place a real entity.

Designing the factory ...

Thanks, that solved the problem.

In 0.17.1 (and previously in 0.17.0) when I attempt to start the new campaign (I click 'Play' -> 'Start Campaign' -> 'Play', with 'Introduction' selected -> 'Play', with 'Arrival' selected) I get an error message:

Notice

Error while applying migration: Base Mod:
2015-07-02_Factorio_0.12.0.lua ...