Custom Post Types is very useful way to add Custom Manager in the WordPress. I have been using More Types with lot of success.
One of the problem that I usually get while setting up is the permalinks structure for the custom post using More Types Plugin or any other Custom Post type plugin is the 404 (Page Not Found) error.
Your custom post type URLs will only work when you re-save your current permalinks structure.
Go to WP Admin > Settings > Permalinks and re-save your current URL structure. This will flush WordPress’s current permalinks URL structure and add our new custom post type rewrite rules. Make sure yuo each time you update the permalinks base inside More Types custom post type, you re-save your WP permalinks structure.
Hope that helps.
Cheers!