To start, you'll have to download and install the latest version of the Audeze HQ app
here, and get the old version firmware
here.
Before you begin updating, make sure you back up any EQ profiles you've created as they will be lost when the firmware is rolled back.
Once installed, plug in your Penrose via USB and unplug the dongle. Open the software and navigate to the "settings" tab of the Penrose profile.
From there, click the "version number" 5 times to open a secret dialogue box.
Load in the .xml file linked above and click the "update firmware" button to begin the update process.
NOTE: you may need to restart both your headphones and the HQ software/computer for your headphones to be recognized by HQ.
You can then upgrade once more to the newest version by either going through the HQ app for Android or restarting the HQ software for PC or Mac. This can help clear up any installation issues that may have occurred during the initial firmware installation.