I created some custom types which are used by custom forms and I discover that the content created by my custom forms can't be listed in the Manage Content, my custom content is not present in the select because I have unchecked the Creatable option of my custom type.

Seems a bad choice ?

Is there any way to present an Admin menu item to list this content ?

Sure, look at how it's done for blog posts, for example.

Pretty good.....but it seems I must write code :), this is my ultimate option on my timeframe.

No way to do it from user interface ?

If you have used a Custom Forms, then go to Forms, then Submission for this type of form.

Oui. Evident.

I am slow on adoption :)

thanks