re-install baseportal

My client purchased baseportal and had it installed and running on his website. Circumstances led to us bringing the website down before we could do an uninstall of baseportal from that website.

We now wish to re-install baseportal on a new website, but are unable to. If we try to run the original installation using the private key, it first fails because it cannot create directories. When we manually create the bp directories, it does populate them, but then ends and says simply "cannot install".

If we try to restore our backup from the original site, baseportal says "wrong domain" and terminates.

What are the remedies that are available to us to re-install on a new website?