That's OK, Tsunami's not a bad last name 😛
The steps I had listed were for a JBoss install. A WebSphere install is much more involved and complicated. It really wouldn't be possible to post a simple list of steps like I did before. My best advice would be to follow the steps in the install guide very carefully.
In order to authenticate into the web client it needs to be set up to authenticate against something. I believe the install guide cover setting it up against LDAP, but you could also set it up in Websphere to authenticate against a local OS account. So no, LDAP isn't 100% necessary, but it's probably recommended.
If you're still having trouble after reinstalling, you can try posting the stack trace from the log file here, or you could open a case with support if you have a maintenance plan or an AEDP membership.
Chris
Adobe Enterprise Developer Support