millwall,

Do you know about adding repositories? For example, to install claws-mail on a 770 you have to have add the following repository:

Address: http://www.claws-mail.org/maemo
Distribution: mistral
Components: user

Without this repository it won't install. Also, I believe in most cases, if not all, you need to have a live Internet connection while installing, not just to download the install file. Hope this helps.