Migrating from Evolution to IceDove

I used Evolution because I prefer to use the defaults whenever possible.
I have a few questions about migrating to Trisquel 8, which will involve
switching to IceDove.

Settings

How do we migrate our settings from Evolution to IceDove?

HTML

Does Trisquel's IceDove make you go thru a bunch of settings to turn off
all the HTML email garbage, just like Thunderbird?

Message Preview

I don't like message preview pains in email clients. How do I turn it
off in IceDove?

Shortcuts

In Evolution, I read one message after the other by clicking on the
first message in the group of messages I want to read and rapidly going
thru them all with the keybard by pressing Ctrl+PgDn (or Ctrl+PgUp if I
need to go back.) How do I do this in IceDove? (A certain proprietary
email client I use at work does not have this keyboard shortcut, and it
annoys me ALL DAY.)

In Evolution, when I'm done composing my message, I quickly send the
message and close the composition window simply by pressing Ctrl+Enter.
How do I do this in IceDove?

Message Headers

Evolution and IceDove insert newlines into long "Subject:" lines in
message headers. This breaks Stallman's email wget script, making it
fetch a partial, incomplete URL, returning an error every time.

The message composition mode in Emacs does not break subject lines like
this. Neither does the Webmin email client I use on bluehome.net. It
only seems to be desktop email clients like IceDove and Evolution that
do this.

How do I make it stop breaking my Subject lines? Or, alternatively, can
someone teach the wget script to understand how to ignore or correct the
newlines?