The only thing I would correct:
If you copy something out of Scapple and paste the text into Scrivener, you get a bunch of unwanted unneeded garbage.
Example:
{\rtf1\ansi\ansicpg1252\uc1\deff0{\fonttbl{\f0\fnil\fcharset0\fprq2 Courier New;}}{\colortbl;\red0\green0\blue0;\red255\green255\blue255;}\paperw12240\paperh15840\margl1800\margr1800\margt1440\margb1440\fet2\ftnbj\aenddoc\pgnrestart\pgnstarts0\pard\plain \ltrch\loch {\f0\fs28\b0\i0 This is a test.}}
The workaround I’ve been using is to paste it into a text document then copy from that and put into Scrivener.
Likewise if you go the other way (Scrivener into Scapple) it annoyingly tries to keep the text size and font you had there.
I’d like it if there was a setting you could use ‘copy as text only’ from both sides. It would save a lot of copy/pasting.
And also, I’d love to be paid to advertise this on my podcast. 
Great products.
Thank you,
Logan