Hi there.
+1. I have the same issues. And it’s seems like some glitch after plugin’s last upgrade.
@nathanhornby, i don’t know help it to you or not and did you see that setings.
Check out this place – in Option menu of wordpress find Languages. Open third tab (Settings) and find first module. It called something like “Modify URL”, dont know exactly, i have no english lang in administration panel. Click on configure link and in right side it have some settings. May be it’s that you looking for.
Sadly, changing this settings don’t help with static redirect problem.