Implementing l10n in an extension

Hello world, 

I've implemented a Calc extension that includes some dialogs and I'd like to 
have those translated to multiple languages. The dialogs are implemented in 
this funny .xdl Basic format, the handlers in Java.

However, as you might've already expected ;) l10n didn't quite work out so 
far. No matter what I do, I can't get localized strings displayed. Instead of 
English or German strings, I see only the references e.g. 
"&3.Dialog1.CommandButton1.Label"

It has certainly something to do with the fact that I've created l10n files 
manually, since GUI for that is currently completely defunct due to [1] so if 
anyone can spot an obvious mistake, something missing etc. in my data below 
and/or give me some useful advice, I'd be grateful

My folder structure:

dialogs/
  +- Dialog1.xdl  
  +- Dialog2.xdl
  +- DialogStrings_de_DE.properties  
  +- DialogStrings_en_US.default  
  +- DialogStrings_en_US.properties  
  +- dialog.xlb

Dialog1.xdl:

<dlg:button dlg:id="CommandButton1" dlg:tab-index="0" dlg:left="98" 
dlg:top="261" dlg:width="32" dlg:height="10" 
dlg:value="&amp;3.Dialog1.CommandButton1.Label">

DialogStrings_en_US.properties:

3.Dialog1.CommandButton1.Label=Close

DialogStrings_de_DE.properties:

3. Dialog1.CommandButton1.Label=Schließen

dialog.xlb:

<library:library xmlns:library="http://openoffice.org/2000/library"; 
library:name="dialogs" library:readonly="false" 
library:passwordprotected="false">
 <library:element library:name="Dialog1"/>
 <library:element library:name="Dialog2"/>
</library:library>


[1] https://bugs.documentfoundation.org/show_bug.cgi?id=93592
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Katarina Behrens

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