Is there a way to create a macro that will force add a carriage return at the end of each line of text, but which will skip lines that have an existing carriage return, such as at the end of a sentence? And, once complete, add a blank line after each line of characters? Please note, double space will not work.

It's an odd request, I know, but context may help:
I prepare scripts to be displayed on an open captioning sign (example here, though I'm not associated with the Kimmel Center). The sign requires a program that can only read text formatted to specific requirements. These requirements can mostly be handled by a Word template and standard formatting tools (e.g., font, size, width, all caps), with the exception of two: first, automatic carriage returns cause an error so there must be a manually entered return, and second, each line of text, including blank lines, must be followed by a completely empty line that includes a carriage return. Double space isn't read as an empty line when imported into the sign's display program, so I can't use that. Also, we sometimes have carriage returns already entered at the end of each line to improve readability or to mimic actor delivery, these can't be doubled. Any help is hugely appreciated. I spend HOURS just hitting 'enter' for some performances!

EXAMPLE:

To have the following display correctly on the sign, these lines:
RICHARD: Now is the winter of our discontent
Made glorious summer by this son of York;
And all the clouds that lowered upon our house
In the deep bosom of the ocean buried.


... must be formatted like this:
RICHARD: NOW IS THE WINTER

OF OUR DISCONTENT

MADE GLORIOUS SUMMER BY

THIS SON OF YORK;

AND ALL THE CLOUDS THAT

LOWERED UPON OUR HOUSE

IN THE DEEP BOSOM

OF THE OCEAN BURIED.