Modifying annotations does not work when....

[nquenouille]

• ... it is an abbreviation (no modification possible at all)
• ... the tag has more than one attribute AND the attributes in question are used in other tags as well

What works:
Multiple unique attributes

annotate.html

<div class="annotation-form date">
      <paper-input name="when" label="when" type="date"/>
      <paper-input name="from" label="from" type="date"/>
      <paper-input name="to" label="to" type="date"/>
      <paper-input name="notBefore" label="notBefore" type="date"/>
      <paper-input name="notAfter" label="notAfter" type="date"/>
</div> 

annotation-config.xqm

case "date" return
      <date xmlns="http://www.tei-c.org/ns/1.0">
      {
          for $prop in map:keys($properties)[. = ('when', 'from', 'to', 'notBefore', 'notAfter')]
          return
              attribute { $prop } { $properties($prop) },
          $content()
      }
      </date>

One attribute, even if its key is a key to attributes in other tags as well ("target" is used as attribute in other tags as well)

annotate.html

<div class="annotation-form ref" data-i18n="[label]annotations.reference">
       <paper-input id="ref" name="target" label="target"/>
</div>

annotation-config.xqm

case "ref" return
   <ref xmlns="http://www.tei-c.org/ns/1.0" target="{$properties?target}">{$content()}</ref>

What does not work:

With only the "expan" attribute or two attributes (like "expan" and "type") - it does not matter, it does not work at all
annotate.html

<div class="annotation-form abbreviation" data-i18n="[label]annotations.abbreviation">
      <paper-input name="expan" data-i18n="[label]annotations.expansion" label="Expansion"/>
      <paper-input name="type" data-i18n="[label]annotations.type" label="Type"/>
</div>

annotation-config.xqm

case "abbreviation" return
      <choice xmlns="http://www.tei-c.org/ns/1.0">
          <abbr>
                {
                for $prop in map:keys($properties)[. = ('type')]
                return
                    attribute { $prop } { $properties($prop) },
                $content()
            }
         </abbr><expan>{$properties?expan}</expan>
      </choice>

With two attributes AND attributes where the key name is used elsewhere as well (like the "type" or "target" attribute)

annotate.html

<div class="annotation-form rs" data-i18n="[label]annotations.rs">
      <paper-input name="type" label="Type" />
      <paper-input name="key" label="Key" />
</div>

annotation-config.xqm

case "rs" return
    <rs xmlns="http://www.tei-c.org/ns/1.0" type="{$properties?type}" key="{$properties?key}">{$content()}
    </rs>

annotate.html

<div class="annotation-form gloss" data-i18n="[label]annotations.gloss">
      <paper-input name="target" label="Target-Id"/>
      <paper-input name="type" label="Type"/>
</div>

annotation-config.xqm

case "gloss" return
    <gloss xmlns="http://www.tei-c.org/ns/1.0">
        {
        for $prop in map:keys($properties)[. = ('target', 'type')]
        return
            attribute { $prop } { $properties($prop) },
        $content()
    }
    </gloss>

Curiosum:

<div class="annotation-form term" data-i18n="[label]annotations.term">
     <paper-input name="xmlid" label="xml:id" />
</div>

The "curiosum" (where I had to omit the colon in attribute xml:id) shows that in the anno:modify function (annotations.xql) the $key is taken from the name of the text-input field in annotate.html (see above), but not from the hard coded tag in annotation-config.xqm (and yes, I use term as a simple tag, not with the register):

annotation-config.xqm

case "term" return
     <term xmlns="http://www.tei-c.org/ns/1.0" xml:id="{$properties?xmlid}">{$content()}</term>

annotations.xql

case element() return
        if ($node is $target) then
            element { node-name($node) } {
                map:for-each($annotation?properties, function($key, $value) {
                    if ($value != '') then
                        attribute { $key } { $value }
                    else
                        ()
                }),
                anno:modify($node/node(), $target, $annotation)
            }
        else
            element { node-name($node) } {
                $node/@*,
                anno:modify($node/node(), $target, $annotation)
            }

I hope, I could explain it well. If not, feel free to ask.
Please, could anyone help here to get this right? I made my first steps in xQuery only last year in October, and I do not have the experience to change the lib code (and do not want to change it, since it is a library that gets updated with new versions).

Many thanks in advance!!!