[chaley]

Three solutions. I used #series for #readorder.

1) Use GPM and the template function:

program:
	if field('#series') then
		 template('Reading List: {#series} #{#series_index:0>2s}')
	fi

2) Use a normal template, which is probably a bit faster than 1) because it avoids the nested template call

{#series:|Reading List: |}{#series_index:0>2s| #|}

3) Use GPM but avoid the call to template(). This will be the fastest if it is used as a rule or a composite column template.

program:
	f = field('#series');
	if f then
		strcat(
			'Reading List: ', f, ' #', 
			format_number(field('#series_index'), '0>2d')
		)
	fi