0.7.4 is not the latest (the latest is openttd 0.7.4-1maemo3). You most probably downloaded the one on the front page of this topic which is for the N8x0. I've already removed it.

Uninstall everything related to OpenTTD and download it from the application manager, games category.

(I have to wonder who allowed direct installation of .debs on a platform _without_ "fat-debs". Hey, maybe I should try to do fat-debs... hm... )