First of all, thank you very much for using this plugin.
If you encounter a 404 error after publishing your MyLinks page, please reset the permalinks by following these steps:
Dashboard => Settings => Permalinks => click the Save Changes button without having to change anything.
The plugin already has a function to automatically flush the permalinks upon activation and page published, but sometimes it’s still not working perfectly as intended.
I’m still looking for the solution.
I kept trying and trying to no avail, but found that changing my permalink settings to ‘Post name’ instead of a custom structure with the category and then the post name worked. It’s a shame though because it means that I have to update all of my posts to this structure, but it will have to do for now.
Thanks for all the work you’re putting into this plugin – it’s really useful and I’m planning a post/video talking about it!