Document Seamless .co2 paths and fix process-name false positives.

Record Jorg desk compatdata locations for satellite setup; devices list terra; tighten watchers so syncgames argv is not mistaken for Eden.

Co-authored-by: Cursor <[email protected]>

docs/add-game.md

@@ -20,6 +20,18 @@ Effects:
 
 Multiple `--paths` allowed. Globs are expanded at session time.
 
+### Seamless Coop (Souls / Elden Ring)
+
+Modded saves use **`.co2`**, not vanilla `.sl2`. Non-Steam / me3 launchers create a **new** Proton `compatdata/<id>` — not the vanilla Steam AppID folder.
+
+See **[seamless-save-paths.md](seamless-save-paths.md)** for discovery steps and known Jorg desktop paths (reference for satellites — always re-find on each device).
+
+```bash
+find ~/.steam/steam/steamapps/compatdata -name '*.co2'
+```
+
+Point `paths` at the directory that contains the `.co2` (per machine — the compatdata id can differ on `terra` vs `Jorg`). SteamID subfolders usually match across devices on the same Steam account.
+
 ### Platforms
 
 | Value | Meaning |

docs/seamless-save-paths.md

@@ -0,0 +1,41 @@
+# Seamless Coop save locations
+
+Seamless Coop does **not** use the vanilla Steam save slot as the live character file. It uses a separate extension (usually **`.co2`**) so co-op progress cannot corrupt `.sl2`.
+
+When the game is launched via **me3**, a **non-Steam Steam shortcut**, or a copied Proton prefix, Steam creates a **new** `compatdata/<random_id>/` — **not** the vanilla AppID (`1245620`, `374320`, …).
+
+## Discover on any device
+
+```bash
+find ~/.steam/steam/steamapps/compatdata ~/.local/share/Steam/steamapps/compatdata \
+  -type f -name '*.co2' 2>/dev/null
+```
+
+Point SyncGames `paths` at the **directory that contains** the `.co2` (the SteamID / account subfolder). Do this **per device** — the numeric `compatdata` id often differs between `Jorg` and `terra` even for the same mod launch method. The SteamID folder name is usually stable on one Steam account.
+
+## Known locations (Jorg desktop — reference only)
+
+| Game id | Compatible discovery | Path used on Jorg |
+|---------|----------------------|-------------------|
+| `elden-ring-seamless` | `ER0000.co2` | `~/.steam/steam/steamapps/compatdata/3917582188/pfx/drive_c/users/steamuser/AppData/Roaming/EldenRing/76561198026393392` |
+| `dark-souls-3` | `DS30000.co2` | `~/.steam/steam/steamapps/compatdata/2678480877/pfx/drive_c/users/steamuser/AppData/Roaming/DarkSoulsIII/0110000103f10730` |
+| `dark-souls-2-sotfs` | *(no `.co2` on Jorg yet)* | Still template vanilla path — replace after first Seamless launch |
+| `dark-souls-remastered` | *(no `.co2` on Jorg yet)* | Still template vanilla path — replace after first Seamless launch |
+
+Older / alternate prefixes may hold conversion leftovers (e.g. `ER0000.cnv.co2` under `3182145933` on Jorg). Prefer the newest live `.co2`, not `.cnv.co2`, unless you intentionally migrate.
+
+## Satellite checklist (`terra`, …)
+
+1. Install AppImage; Setup → same MinIO keys; **`device_id = "terra"`** (or that machine’s id).
+2. Seed/add games; run the `find … '*.co2'` command above.
+3. Edit each game’s path to **this** machine’s directory (GUI Load → Save, or `syncgames edit`).
+4. **Start** → pulls SSOT into the local Seamless folder → play → **End**.
+
+Optional automation after paths are correct:
+
+```bash
+./systemd/install-user-units.sh
+# ensure syncgames is on PATH, e.g. symlink AppImage CLI or pip install -e
+systemctl --user enable --now [email protected]
+systemctl --user enable --now [email protected]
+```