What am I doing wrong?

[Barrie Stott]

I want some text to have the following format.

--------------
This represents text before the stuff I am talking about

    {{   Here are paragraphs of text with all the
         usual things such as lists and displays.

         There can be several paragraphs in this
         block of text we are in.
    }}

This follows the stuff I am talking about.
--------------

I can almost get what I want by using

@LLP |1c {"{{" |1c {
Paragraphs of text with properly nested {}
} ^/ "}}"}

Unfortunately, if the block of text will not fit on the current page, the
whole of it goes on the next page. How can I prevent this?

Thinking that the outermost set of {} was binding things too tightly for what
I wanted, I removed them but then got the error message:

internal error: assert failed in FlushGalley: dest_side != FWD ||
!is_indefinite(type(y))!

Any assistance would be greatly appreciated.

Barrie.