Europa Barbarorum is a total conversion modification. The modification affects all areas of RTW; all vanilla units have been removed, all new models and textures, a new economic system, new traits system, new scripts, and in general new gameplay. No area of RTW is left untouched.
Roma Surrectum 2 is a full conversion mod to Rome Total war 1.5 and the predecessor to the original Roma Surrectum mod featuring unique Roman legions, new factions, units and a stunning high detailed map. Roma Surrectum 2 is developed for Rome Total war, but it will also run on both of its expansions, Barbarian invasion and Alexander.
Holland: Total War:
Holland: Total War is a conversion mod for Rome: Total War, and is based upon the Netherlands. As the mod is unhistorical, it is still fun to play. This mod includes a total rework of map, unit and faction editing. The playable factions are the Dutch provinces and factions around the Netherlands (like France, British and some German provinces). The mod is free to play and the owner is still working on updates for the mod.
<path-to-game>\Rome Total War Gold\data\fmv
You have installed Rome Total War on a 64-bit system, but there is a bug in the installer which installs the game files in the wrong location by default. The incorrect default location is C:\Program Files; the correct location to install these files is C:\Program Files (x86). To fix this uninstall Rome Total War and all its expansions and patches, then freshly install the game again, making sure to installer selects "C:\Program Files (x86)" to install the game to. Warning: uninstalling the game and its expansions and patches will delete any saved games, the save game data folders should be copied to another destination and replaced after the fresh install.
C:\Program Files (x86)
Copy steam.dll from the main Steam folder into the Rome installation folder. This is a fix that most likely will fix your problem.
If neither of these methods work or if you are getting a "Steam failed to start" message, exit Steam then right-click the Steam shortcut and choose Run as administrator.