Arg, this must be a dumb question since no one has answered it yet, but I have the same question.

I remember reading somewhere that a file needs to be edited, but i can't find the instructions anymore.

To delete an install do:
1) delete all files that were installed
2) delete database entries

1) go to the folder where you installed B2e with your davorite FTP manager (like WS FTP) or throufh your hosts cpanel or phpMyadmin (choose file manager or the like) and delete the files and folders:
- conf
- cron
- plus all folders that are made on the same date and time as these (12 folders) plus:
- _header.php
- admin.php
- and all files that are made on the same day and time as these (plm 11 files in version 1.9.2)

2) In phpMyAdmin or cpanel provided by your host, enter the database and delete every entrie that starts with evo_. There sould be quit a few. You could do a delete all if you don't use the database for other purposes, but if you do use the database: be carefull.
Mind this: do not delete the database itself, only the entries.

Good luck.