By 'quick insert' and 'main', I do indeed mean the main Site Sculptor dialog accessible under WebAssist > Build Site. Quick insert is meant to explain the new structure we have were there is a simplified interface you see at first, then you can click Define buttons to view the more complex interfaces if you need to customize it more.
Here a few docs that should help out with your other questions.
siteassistpro_update_sculptor_mw_ht.pdf (SiteAssist Pro PDF, but still relevant)
Some of the documents for SiteAssist Pro might help out too. They won't correspond exactly to Site Sculptor, but the docs about create site designs and preparing your DW templates should give some good starting info. siteassist/
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