Ready
to play.

A few seconds after startup, the mod checks for a new version. By default it only notifies you: you decide whether to download it, and it takes effect when you restart the game. Before offering it, the mod verifies the package's signature and hash. If the new version fails to reach the menu on three starts in a row, the mod restores the previous one (kept as <code>winmm.dll.previous</code>) and tells you.

You can change this in imperivm-mod.ini, section [Updates]: Mode=notify notifies, Mode=auto downloads and installs, Mode=off doesn't check at all. To update by hand, with the game closed, extract the new zip over the existing install: the .ini is kept.

Close the game and delete winmm.dll from the game folder. The game goes back to the original: the mod doesn't modify gbr.exe. Your settings stay in imperivm-mod.ini and your additional content in the mods folder, in case you reinstall; delete them if you don't want them. To remove a single content package, use Uninstall in Additional content.

In imperivm-mod.ini, in the game folder. The zip doesn't include it, so updating keeps them. It's where you change, for example, how often the game autosaves (AutosaveMinutes, 10 by default) or turn off Discord presence (Presence=0).

Close the game and create the report (next question). Note what you were doing right before it failed. The logs are in Logs\imperivm\, inside the game folder; the mod keeps the last five sessions.

To find out whether the mod is the cause, delete winmm.dll and repeat what you were doing. If the original game also closes, the mod isn't at fault. The mod already fixes some crashes of the original game, such as those in the map editor and in certain map scripts.

In the main menu, click the heart and then Create report. A zip is created in Logs\imperivm\reports\ with the logs and details of your machine (system and graphics card). It masks your SteamID64, IP addresses, Windows username and Steam names.

The mod sends nothing: you attach the zip yourself wherever you ask for help, and you can open it first. One limit: player names from earlier sessions may be left unmasked (the report itself warns about this in a note), so check the contents before sharing it.

The mod is the file winmm.dll: a DLL the game loads on startup. It isn't signed with a code publisher certificate (Authenticode) and there is no installer, so SmartScreen or your antivirus may warn about it or quarantine it.

Updates do carry a project signature, but the mod itself checks it; it isn't a signature Windows recognizes and it doesn't prevent the warning. The code is public on GitHub if you want to review it. Download only from the repository's releases page and compare the SHA-256 with the SHA256SUMS.txt file attached to each release. If you don't trust it, don't install it: removing it is just deleting a file. If your antivirus quarantines it and you decide to trust it, restore the file and add an exclusion for that file only.

Yes to both. Anyone without the mod can't play in your rooms, or watch them as a spectator. Everyone must run the same version and the same gameplay content; content that is only cosmetic, graphical or text doesn't count. The network protocol changes between versions, which is why they can't be mixed.

No. Games go through Steam's network, with no ports to open. Everyone needs the game on Steam and Steam running.

There is no quick match, ranked play, ranking or server of its own: you play in rooms, with friends. Performance isn't guaranteed on slow computers or while sharing your screen on Discord.

Yes, with spectator mode. In Multiplayer, rooms in progress show a Watch the game button. The broadcast runs delayed, 30 seconds by default, and comes with a bar for pause, 10-second jumps, a timeline, x1 to x8 speeds (only if you're behind) and returning to live.

You can't switch player and there's no chat between spectators, and spectators also need the mod on the same version. The same bar works with replays saved on your computer: jumping back reloads and fast-forwards, so it takes a while.

You can try the Return to the game button: the dropped player reconnects without the others leaving, and the game pauses for a few seconds. It isn't guaranteed. The host decides and can refuse (for example, if the AI already controls your slot), and the original game counts someone as dropped after about 30 seconds without traffic.

The Additional content button in the main menu opens the manager. It lists what's installed, enables or disables each package, shows its dependencies, opens the folder, installs a .zip by hand and uninstalls (the package goes to the recycle bin). Profiles save a combination of active packages: you can save one under a new name, rename it and delete it. My content is the state with no profile. Load order is automatic.

The Browse content tab is a GameBanana catalog: search, categories, filters by type, number of players and language, dependencies, update notices and a button to update everything. The manager warns when two packages touch the same files or override each other's values, but it doesn't resolve the clash or guarantee that packages from different authors are compatible. A package containing executables or system scripts isn't loaded.

Large packages can take a while to download.

Yes. Ctrl+T opens the cheats panel: gold, food, population, map, heal, ration, delete, level, spawn troops, research technologies and a few more, also on several selected units. In a room, the host decides whether they are allowed with the “Allow cheats” option. If they do, the cheats are synced with everyone, who need the same mod version.

Open a GitHub issue or ask on Discord, the Imperivm III editors' community server. Attach the report zip, the mod version and what you were doing when it failed.

This is a hobby project with no official support. It isn't affiliated with FX Interactive or Haemimont Games.