Hey, Paul...
If it looks like embedding 5.4 would work well, but you're concerned
about the performance issues of having many instances, perhaps you
could do something like having a regular text box for each value and
wiring things up so that when the focus shifts to one of those boxes,
a single instance of the Editor control is positioned on top of the
text box, loaded with its content and made visible. On loss of focus,
the content is shifted back to the text box and the Editor is hidden.
The effect would be one of the Editor kind of "coming to life" as they
move to each field.
Alternatively, especially since you're not on 5.4 yet, you might
consider doing something with a rich text control. Your description
of the content model seemed to indicate that it is pretty much the
same for all of the fields, consisting of mixed content with two empty
tags and two inlines (bold and italic). Assuming that the empty tags
can occur inside the inlines, you could probably enable bold and
italic in the rich text control, giving the user buttons and/or
keyboard shortcuts to activate them, make the control multi-line so
the user can insert a "newline" directly, and allow insertion of the
"check" through whatever mechanism feels right, representing it in the
field with a character whose glyph looks about right.
If the input is limited, which should not be too hard, it should be
fairly easy to keep them from making something invalid and it
shouldn't be too complicated to parse the result, turning actual
newlines into the element form, your chosen special character into the
check element and stretches of bold and italic into the inline tags.
This does have a certain amount of reinventing the wheel attached to
it, but given the minimal structure involved, it may provide a
lighter-weight solution than embedding the full Editor control, and
you could do it with the version of Editor you're using right now.
-Brandon 🙂