Seriously guys, I don't get this complaining about timing. Noone is forcing you to abandon your 1.0 campaign. Just make a new copy of RTW 1.5 and install EB 1.1 into that, and you have separate installations of both versions.

The Casse invasion is a scripted invasion of Belgium when the AI is Casse and has taken all of Britain and Ireland. We hope it will make the AI Casse more interesting in spite of the AI's aversion to naval invasions.