Add custom widget multiple times

Hello,

I was wondering if anyone has tried the following scenario :
I have a page on which the user can add both widgets from sf as well as my widgets, as many times as he/she wants.

1. How can I add custom fields to my widget (like the ones we can see on Blog post widget: input fields, radio buttons, uploaders and  category/pages selectors).

2. How can I pass on to my widget, on edit, the ID of the placeholder in the page where it should be inserted? I need this so that I can associate data I collect in my widget with a location on the page.

Thank you,

Ancuta

I'm trying to do something similar. To have the ability to add a custom user control when Editing in CMS a widget.

Is it possible to do this and how? I didn't find any resources on this.