Hi there
I have the same issue with a template I just bought for wp + woocommerce… a nice template indeed BUT have problem after 80 items in the menu… deleting the old one.
So is not an installation issue BUT a theme issue…
Just a suggestion…. but sure not a solution…
1) Create the custom menu using a default theme of wp like twentyten
and save
2) Change the theme using your favorite one and the menu saved will be there…. be careful not save again the menu or will be gone
3) Regretfully need to remember to switch theme before modify and save the menu…
