You don't need appserver for ANYTHING... appserver is simply a collection of free programs including apache web server and mysql server.
The answer is.. it depends.
5095 binaries and coemu use mysql meaning you can download the sql server from their website (google it >.<) and use a program like navicat or phpmyadmin to edit the databases manually. Then as far as registration scripts go, you set them up using an apache web server to host the website running the script. There are a bunch of them already released on epvp, try searching.
Basically they would just go in your public web folder for apache. To access them just do something like
127.0.0.1/filename.php in your browser. Assuming you have port forwarded port 80 you can give people your external ip to access your website from any browser (
works well enough)