Uninstall EB and then uninstall RTW and try from the beginning.

Install RTW and patch up to 1.5 and then check that vanilla RTW is working. Once you've tested that (no need to go into a campaign), install EB. Make sure that it is installed to the main Rome folder, ie the one with the RomeTW.exe in it (default name is "Rome - Total War"). Also make sure that your windows username does not contain any non-standard latin characters, this includes letters with accents. This often causes the installation of EB to fail half-way through. If you do have a non-standard character in your windows username, create a new admin account and give it a simple name. Install through that username and then delete the account when you have finished. You won't have a shortcut on your desktop so to create a new one, create a shortcut for the RomeTW.exe file. Open the properties window for it and add the following to the end of the target line, after the quotation marks.

Code:
-mod:eb -nm -show_err
When you start it up with this shortcut you should have a flashscreen saying Europa Barbarorum, not Rome Total War.

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