Here's the .dcupdate for one of taichi's plugins, which shows:
<?xml version="1.0" ?>
<Local>
<!-- basic info to display in updater-->
<Label>Network Connections Plugin</Label>
<IconFile>nwconn.ico</IconFile>
<!-- version info of locally installed current version, and simple remote version file -->
<Version>0.0.0.3</Version>
<VersionFileRemote>http://taichi.dcmembers.com/Plugins/NWConnect/versioninfo.xml</VersionFileRemote>
<!-- where to get more info about the app remotely, only queried once an update is discovered -->
<InfoFileRemote></InfoFileRemote>
<WebPage>http://taichi.dcmembers.com/Plugins/</WebPage>
<!-- ok how to conduct updates; could be: "Run" (download and run program), or "Visit" (visit website), or "Unzip" (download zip and unpack over files) -->
<UpdateMethod>unzip</UpdateMethod>
<SignalForUpdate>FindAndRunRobot.exe</SignalForUpdate>
<CloseForUpdate></CloseForUpdate>
<UpdateFile>http://taichi.dcmembers.com/Plugins/NWConnect/NWConnect.zip</UpdateFile>
</Local>
The key new lines are:
<UpdateMethod>unzip</UpdateMethod>
<SignalForUpdate>FindAndRunRobot.exe</SignalForUpdate>
the zip is unpacked into the same directory as the .dcupdate file (thats how it knows where to unzip)
and the <SignalForUpdate> stuff lets it know to tell the FindAndRunRobot.exe at start and end of unpacking to unload any plugins (this is something unique to farr).