Menu breaks down when trying to modify

Hey Atahualpa users,

I was wondering if any of you encountered such a thing... I only have 1 menu on one of my sites. I change some menu items once in a while. My problem is the menu does not update with the changes when I click "Save". Not only that, it also does not remember the Theme Location I assigned to it. I have to Save it a couple of times plus re-tick the menu position for it to finally update.
Also, new items I try to add to this menu simply disappear after I "save" the menu. Normally you should be able to find these new items at the end of the menu (after adding a link as a menu item). I add it there and after saving it's not there. Frustrating I tell you.

Anyone else fighting with this?

Also, are there any limitations for the number of main items on a menu, say 20 or something like that?

Wordpress 3.6 & Atahualpa 3.7.12

Thank you!