How to install it

Five steps, in order.

1. 1
   Put the app in your Applications folder and open it

   Open the downloaded .dmg and drag CullMaster Pro onto the Applications folder sitting beside it, then open it from there. (Upgrading from GoodEye Loupe? Double-click the app on the disk image instead — it replaces the old copy and keeps your settings and cached photos.) It is signed and notarised by Apple, so it opens like any normal app — no right-click dance, no security warning.
   
   A narrow dark panel appears saying “bridge not running”. That is exactly right at this point: the app is running, it just has nothing to follow yet.
2. 2
   Read what the plug-in does, then press Install

   The plug-in ships inside the app, so there is no second download. The first time, the setup guide shows you exactly what it does with a Lightroom catalog and waits for you to press Install; after that, updates to the plug-in are automatic.
   
   Here is everything it does. It reads a catalog file in read-only mode for flags, stars, color labels, and folder colors, and only for a catalog you have marked Sync. When you set a flag, star, or label in CullMaster, the plug-in asks Lightroom to make that change while Lightroom is running, and each change appears in Lightroom’s Edit ▸ Undo. It changes nothing else: no develop settings, keywords, or other metadata, and it never deletes, moves, renames, or imports photos. And it never edits the catalog file directly.
   
   A catalog you open only to look at, such as an editor’s return or a copy you are checking, is left alone entirely. The first time Lightroom opens any catalog, CullMaster asks whether to Sync with it or treat it as Review only. Nothing is read from or written to a catalog until you answer, and you can change the answer any time in File ▸ Lightroom Catalogs….
3. 3
   Quit Lightroom completely and open it again

   Lightroom only looks for plug-ins when it starts, so it will not see the new one until you restart it. Quit it properly (Lightroom ▸ Quit Lightroom), not just close the window.
4. 4
   The bridge starts with Lightroom

   From now on the plug-in arms the bridge every time Lightroom launches, and starts CullMaster Pro if it is not already running. A small window appears saying “Feeding the loupe. Leave this window open.” — that window is what tells the app which photo you are looking at. Push it behind Lightroom if it is in the way, but do not close it.
   
   If it ever does not come up on its own: Library ▸ Plug-in Extras ▸ CullMaster Pro — start bridge.
5. 5
   Click any photo

   The panel fills in — one row per person, cropped at 100% straight from the RAW. The first pass through a photo takes about half a second while it renders; after that it is instant, and it keeps caching the rest of the shoot in the background while your machine has capacity to spare.

Before it gets in your way.

Drop the new one over the old one.

There is no auto-update and nothing phones home. When there is a new version, download it and replace the app in your Applications folder — quit the loupe first, then drag the new one in. Your settings, your window size and position, and everything already cached all carry across.

The Lightroom plug-in is copied into Lightroom’s folder when you press Install Lightroom plug-in, so a new app does not refresh it on its own. If a release says the plug-in changed, press that button again and restart Lightroom. Otherwise leave it alone.

Troubleshooting

Nothing to uninstall, really.

Drag the app to the Trash. Your photos and develop settings were never touched. Any flags, stars or labels you set in CullMaster are already in your catalog the same way you would have set them in Lightroom, so there is nothing to put back and nothing to undo.

Two leftovers, if you want them gone. The plug-in sits at ~/Library/Application Support/Adobe/Lightroom/Modules/CullMasterPro.lrplugin — delete that folder and restart Lightroom.

The rendered crops live in ~/Library/Caches/co.goodeye.loupe and can reach several gigabytes on a heavy month, so clear them before you delete the app — options ▸ rendering ▸ Purge — or delete that folder afterwards.