What is want is pretty simple. I want to add settings to all field-properties (oob and custom) in a custom listdefinition, say "E-mailform". Thus, I create a "E-mailform" and I add a OOB-textfield. At the settingspage (where you can set length, required yes/no, etc.) I want to add a custom section with custom settings. When I add a OOB-numberfield, I want to add this same custom section.
I use SharePoint lists to create webforms and I have adapted the NewForm.aspx to show it in the required layout. However, I have to add settings to the fields, e.g. to make fields appear next to each other instead of all below each other. Thus, I have to extend all field settings with a custom "emailform-property-setting".
I have Googled a lot and the only solution i found is to make custom fields, but that is not what I want...
I hope I explained it well enough!