It wasn' working fine because the wiki_pages table hadn't an id (primary key) field.
I've created, in the upgrade process, a temporary table to copy all the wiki_pages
records and then, drop and create again the table.
Tested under MySQL. Need to be tested (both creation and upgrade) under PostgreSQL!!!
Minor modifications to ewikimoodlelib.php to work with this new id field too. Seems to work
although deeper tests will be welcome (attachements, binary contents...)
Cross your fingers! ;-)
I've left out stuff that didn't seem necessary ... including a lot
of the Wiki plugins which were quote large... I'm not sure if this
is currently working ... I'm about to try it out.