Hi, that’s strange, I haven’t heard of this problem before.
You probably already checked these already, but just in case:
– Make sure you’ve saved the otions
– Make sure the MapPress meta box isn’t hidden for your post type (in the WP editor choose the ‘screen options’ button in the upper-right to enable/disable it)
If that doesn’t work, how are you creating your custom post type? Do you have the register_post_type() code you used?