Deployment of SF 5 site... 404's and login failures

Hello,
I've reviewed the documentation on deploying a sitefinity site, watched a video on it, and I'm having serious issues getting this SF 5 (5.0.2500) site up and running in a new environment.

First off, I tried following what the video suggests (www.sitefinity.com/.../deploying-sitefinity-to-a-webserver.aspx), and deployed my app as normal to the server. This results in constant 404's on the server. Any file I try to navigate to in the directory leads to a 404. If I tried to goto /Sitefinity, I get redirected to /Sitefinity/Authenticate/SWT, which is a 404.

So, I downloaded the project manager, after reading the installation manual, and was able to get an instance up an running on the server. Great, I thought. I went in and changed my connection string, which then gave me the "FrontendSiteNode" error (remedy to that issue here: www.sitefinity.com/.../when-sitefinity-project-is-deployed-to-production-server-an-invalid-root-node-configured-for-pages-no-root-node-with-the-name-of-frontendsitemap-error-is-thrown.aspx). I then went in an modified the projectConfig file, so it matched my sf_page_node table.

Now, I'm able to get to my login screen, but I cannot log in. None of the users that are part of the site that are in the database work. There doesn't seem to be any exceptions occuring, so, what am I missing here?

edit: I have it up an running. I set up the project in Sitefinity Project Manager (on the server), making sure to give the same name as the database I was going to tie it to was expecting. Then, I copied my config files (App_Data/Sitefinity/Config) from my deployed site to my newly created site, being sure not to overwrite the Projects and Security config files which had been created by the sitefinity project manager. Then, I tried to load up the site, got a permissions error on App_Data, so, I added modify permissions to that directory for the IIS User acount, and now it works. However, given previous trials, I'm pretty sure this is going to break the next time I attempt to publish all my files, as simply overwriting the files in that new project folder with my deployed site resulted in the constant 404 issues I described above. What is responsible for the 404's? Perhaps that will help me to determine what it is that causes the issue when i deploy.

I was right, it broke the next time I published.