Many thanks Boban, that solved it!
Best wishes,
Andrew
Removed and re-installed 1.33, but alas, same result! Checked for clash with other plugin by disabling all others and also tried temporarily replacing my Weaver theme with wp 2013, still 500 in each case though.
Andrew
My site has run happily for months. Upgraded to version 1.3.3 and WP 3.6.1 and now editing any post results in a 500 error. Once MP is deactivated, all works fine. Any thoughts?
Many thanks for an (otherwise) great piece of software!