Installing StemForge

StemForge has two parts: the desktop companion app (does the actual audio processing) and the Premiere Pro plugin (the panel you use inside Premiere). Install both, in either order, but start the companion app at least once before using the plugin.

You'll need: a Mac, Adobe Premiere Pro 2026 (version 26.0 or newer), and the Creative Cloud Desktop app installed and signed in.

Download

1. Use the Download StemForge for Mac link in your purchase email, or on the page you saw right after checkout. (Haven't bought it yet? Get StemForge.)
2. Double-click the zip in Finder to unzip it. You'll get a folder with:
   • StemForge.app, the desktop companion app (step 1)
   • StemForge-PremierePlugin.ccx, the Premiere Pro plugin (step 2)
   • Install Premiere Plugin.command, a backup plugin installer if double-clicking the .ccx doesn't work
   • READ ME FIRST.txt, a short version of this guide
3. Move the folder out of your Desktop (Downloads is fine) before installing. Installing the plugin from the Desktop can fail.

1. Install the desktop companion app

StemForge isn't yet signed with an Apple Developer certificate, so macOS Gatekeeper will warn you the first time you open it. This is expected:

1. Drag StemForge.app into your Applications folder, then double-click it.
2. macOS says it can't verify the app is free of malware, with only "Done" or "Move to Trash". Click Done.
3. Open System Settings, then Privacy & Security.
4. Scroll down to the message that StemForge was blocked and click Open Anyway.
5. Confirm with your Mac password or Touch ID.
6. StemForge launches in your menu bar and asks for your license key (from your purchase email). On first launch it downloads its audio-separation model (~80 MB).

StemForge starts automatically when you log in, so you normally only do this once.

2. Install the Premiere Pro plugin

Before you start, check you have Premiere Pro 2026 (26.0+) by choosing Premiere Pro > About Premiere Pro, and that the Creative Cloud Desktop app is installed and signed in. It's what actually installs .ccx plugins.

1. Find StemForge-PremierePlugin.ccx in the unzipped folder. Don't install it from your Desktop.
2. Double-click it. Creative Cloud opens and shows "Install a non-marketplace plugin."
3. Click Install, then OK on the permissions notice, and enter your Mac admin password.
4. You'll see: "StemForge is now installed. Find it under the Plugins Menu in Premiere."

If double-clicking the .ccx doesn't work

Keep Install Premiere Plugin.commandin the same folder as the .ccx and double-click it. It checks your Premiere and Creative Cloud install, installs the plugin with Adobe's own installer, and tells you exactly what's missing if anything is. macOS blocks it the first time too, so use Open Anywayin Privacy & Security as above, then restart Premiere.

3. Open the plugin in Premiere Pro

1. Open Premiere Pro.
2. Go to Window > UXP Plugins > StemForge (not "Extensions").
3. If the status dot is red/offline, make sure the StemForge companion app is running in your menu bar.

Troubleshooting

• ".ccx won't open, error code -3". The file is probably on your Desktop. Move it to Downloads and try again.
• Double-clicking the .ccx does nothing. Creative Cloud Desktop is missing, signed out, or out of date. Update and sign in, or use Install Premiere Plugin.command.
• StemForge isn't under Window > UXP Plugins. The install didn't complete, or Premiere is older than 26.0. Run Install Premiere Plugin.command and fully restart Premiere.
• Plugin panel shows "offline". The companion app isn't running. Relaunch it from Applications.
• Gatekeeper won't let you open the app. Click Open Anyway within a few minutes of the blocked attempt. If the button is gone, try opening the app again to make it reappear.
• Premiere wasn't installed through Creative Cloud. StemForge only supports genuine Premiere Pro installed through Creative Cloud.