The forum post
http://www.thehiddenforest.org/forum/viewtopic.php?f=7&t=3266 should help you setting up an account for the first time.
You need to create a login account to login via everquest. This is different than
a forum account. Best to create one via eqemulator.org. Once you are in-game you can create a private login account that covers you should the public login servers go MIA.
THF server uses the public (eqemulator.org) and also allows you to login via its own private server. The forum post explains how to create a public/private forum and what files to change in order to use them.
Also dont forget to update the custom files on your client. Allways best to make a copy of your install directory so you have an original copy. If you are coming from another emulator server that uses custom files, its allways best to use a vanilla install, as some issues can arrise with other peoples customs files.
Lots of posts on the forums allready about using MacroQuest. Get your client working first, then all you need to do is just run the MQ.exe and it wil become obvious. It will either create a new MQ chat window or it will give an error (wrong client etc).