Downloading Argena 2.1 for Mac from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this app available. This Mac app is a product of EZ-ComSite, Inc. The application lies within Developer Tools, more precisely Webmaster Tools.
From the developer:
Argena is a multilingual website editor managing up to 9 languages as easily as only one. Each Text, object, product includes its own translations. It has totally integrated Web tools, offers an object oriented Web page editor, totally WYSIWYG, associated with a graphic workshop.
You may want to check out more software for Mac, such as AcidSearch Installer, Browsealoud or RAGE WebDesign, which might be similar to Argena.