Virtue,

When you say
I am still working on this (as this is my project) and suddenly I got that weird screen when I tried to go and check the store.
it is unlikely you will get much help. It is just too vague.

I can only help new zenners with very basic things like the template override. I hope it takes some pressure off the 'big guns' to handle more serious issues.

A problem with the database qualifies as more serious and the only help I can give you is this - to be a specific as possible about the problem. Who does the hosting? what is the exact error message? how did it happen, EXACTLY? etc.

But here's another big error I got. When I tried to configure the SSL to link with LinkPoint, it doesn't save my changes.

// Use secure webserver for checkout procedure?
define('ENABLE_SSL', 'false');

I am trying to change the "false" to "yes". But it gives me "fatal error or runtime error occured" message and doesn't save the changes.

Is this what is causing it?
I suggest you search for threads on this. I have not dealt with the problem but someone has.

If you don't get some helpful feedback I will PM someone that can likely help. In the meantime, maybe you can work on the content for your custom template and load a test product or two.

i can tell you that I installed and re-installed the cart multiple times at the beginning to get everything set right. I just kept messing something up. After that however, smooth sailing. So don't give up.

Good luck.