Hi, and thanks for your help.
I've built the ePub from scratch using Notepad++ and I'm using dummy content files to get the package working.
I have only one remaining error when I use the online epub validator at
http://validator.idpf.org/, but I can't see the cause.
The error is:
./tmp/uploads/1455200484959_0000117833/inputFile/mybook5.epub/OEBPS/content.opf(-1,-1)
There was an error when parsing the EPUB version: Version not found.
My content.opf starts like this (I've replaced confidential info below with XXXX):
<?xml version="1.0" encoding="utf-8"?>
<package version="2.0" xmlns="http://www.idpf.org/2007/opf" unique-identifier="BookId">
<metadata xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns

pf="http://www.idpf.org/2007/opf">
<!--Required Metadata-->
<dc:title>XXXXXX</dc:title>
<dc:language>en-gb</dc:language>
<dc:identifier id="BookId" opf:scheme="ISBN">urn:isbn:XXXXXXX</dc:identifier> <!--Use the Same for the toc.ncx file -->
<dc:creator opf:role="aut">XXXXXXX</dc:creator>
<dc

ublisher>XXXXXX</dc

ublisher>
<dc:date>2016-03-14</dc:date>
<meta name="cover" content="My_Cover_ID"/> <!--Required for KindleGen-->
etc etc
<metadata>
I see above that code "colon o" got interpreted as an icon above. The original looks ok.
Thanks for your help