MVC1 CROSS FEVER V3 — EXPERIMENTAL PREVIEW

This is a separate game and core from V2.2 and DHC. Teams are now P1 + P2
versus P3 + P4. Do not mix V2.2 and V3 game/core files or netplay participants.

INSTALL
1. Extract the matching platform package to a fresh writable local folder.
2. Supply clean MVC1 Europe 980123 mvsc.zip including its original mvsc.key.
   Windows: drag it onto BUILD.cmd. macOS/Linux:
   python3 install.py /path/to/mvsc.zip
   The installer verifies member contents and writes output/mvsc4p.zip plus
   a receipt. Your original archive is preserved. Do not rename a stock ROM.
   Existing output is refused; extract again to a fresh folder. The Python
   installer requires a local filesystem with hard links (APFS/ext4/NTFS).
3. Install matching 64-bit RetroArch separately. Close it, then run PLAY.cmd
   on Windows or python3 play.py on macOS/Linux. If needed, pass the path to
   retroarch.exe, RetroArch.app or the Linux executable.
4. Verify Information > Core Information identifies
   FBNeo (MVC1 Cross Fever V3), and that the content is mvsc4p.zip.
   The V3 core has a unique filename and does not replace the V2.2 core.

Platform requirements: Windows x64; Linux x64 with Ubuntu 22.04-compatible
runtime; Apple silicon macOS 26+. Build availability is not native-platform
acceptance. See TEST_RESULTS.json for the exact tests actually completed.

CONTROLS
On one computer, Settings > Input > RetroPad Binds must assign a different
Device Index to each of ports 1–4. Check Quick Menu > Controls for remaps.
The V3 core fixes the same RetroPad layout for Classic, Modern and 6-Button
Panel; your explicit RetroArch remaps still apply:
    Y = LP   X = MP   L = HP       B = LK   A = MK   R = HK
    L2 = PPP                     R2 = KKK
These are RetroPad labels, not necessarily the letters on your controller.
Start and Select are not gameplay join buttons. Use HP+HK (default L+R),
then release before confirming. P1/P3 choose the first fighters; P2/P4
choose their teammates and the helper for their team. P2/P4 can hold a native
helper button shortcut through second-fighter confirmation. Releasing allows
the helper roulette; a fresh attack stops it. P2/P4 also choose team order;
the first owner controls the native speed menu. Release the join chord before
character confirmation.
HP+HK tags; QCF+HP+HK is Team Hyper; QCB+HP+HK is Duo (two bars minimum).
During Duo, each person retains their own fighter. Expiry does not make
one person's controls drive both teammates.

TROUBLESHOOTING
- Failed to load: confirm the V3 core name and output/mvsc4p.zip, then run
  CHECK.cmd or python3 diagnose.py. It checks exact files, not just names.
- A controller does nothing: record its Device Index, Device Type and
  Quick Menu remap. Test the six attacks separately before testing chords.
- Wrong teammate: V3 uses P1/P2 versus P3/P4. V2.2 used a different order.
- Startup exits: keep the files in logs/. The launchers save RetroArch's
  verbose log and a support JSON without copying passwords or nicknames.
  For a later Python check, use --config /path/to/retroarch.cfg and
  --log /path/to/log. Add --remap /path/to/mvsc4p.rmp to inspect a remap.
  Windows CHECK.cmd accepts -Config and -Remap. Configured assignments
  are reported as configuration, not proof of attached physical pads.

The launchers preserve RetroArch's preferences. Configure Netplay hosting,
relay/public listing and your nickname in RetroArch yourself. All players
need the same V3 package/game and compatible RetroArch version. A same-host
simulated session does not establish a four-machine internet match.

The measured save/load check preserves all 60 work-RAM replay frames, but
differs in QSound state and the first restored video frame. The exact V2.2
control reproduces this limitation. V3's core info advertises serialized
save states, not full netplay/runahead determinism. See TEST_RESULTS.json.

REPORT A RESULT
Include package version, operating system, RetroArch version, loaded core,
game check, port/device assignments, phase and exact failure. The historical
first report concerned V1; the later report did not identify its core/package.
Do not classify either as a current V3 regression without reproducing it.

Control switching, three-human play and classic shared Duo control remain
separate design requests. This package preserves independent Duo ownership.

Only patch data, source and the emulator core are distributed. No game ROM,
decryption key or save state is included. FBNeo's license accompanies it.
