Multi Url Picker / Link Picker - Single item picker

[bengr...@googlemail.com]

I'm looking for a control that will allow an editor to pick a single Url (internal to the site, or external to the site) or a single link to an image.
The Multi Url Picker has a good interface for this:

https://our.umbraco.org/projects/backoffice-extensions/multi-url-picker

and so does the link picker:

https://our.umbraco.org/projects/backoffice-extensions/link-picker/

The issues:

I can't seem to limit the MultiUrlPicker to only allow the editor to pick one item. Even though the control has properties for "Min number" and "Max number", it doesn't actually seem to stop people adding more than one link.
The link picker is perfect, but once you've added the link you can't edit it, you have to delete and re add.
Does anyone either know how to fix either of those issues, or another control that will do what I want?

Thanks,
Ben