The problem is that the JavaScript "prepareInputsForSubmission(this)", which is in the form's onsubmit attribute, is never called. This happens because the JavaScript from the form's onsubmit attribute is not called when the form is submitted via a commandLink, rather than a commandButton, and the DELETE button is a commandLink. So I figured I would try using the commandLink's onclick attribute to call prepareInputsForSubmission(), i.e. onclick="return prepareInputsForSubmission(this.form);". This almost works, but for some reason, the commandLink's child params are not included in the request that is submitted, and therefore the delete ends up being a no-op. Note, the reason commandLink was used rather than commandButton in the first place is because commandButton does not support child f:params, which were necessary for the DELETE button; a possible alternative is to use a commandButton and f:attributes, which are supported by both commandLinks and commandButtons.

I spent several hours troubleshooting this and wasn't able to get it to work. I think it should be tabled until post-x.2. The workaround is to uncheck and then recheck the Unset checkboxes for any optional integer props before clicking SAVE to update the config. Otherwise, you will see validation errors for those props saying "" is not a valid value for integer property 'foobar'.