Draw AP Div tool - objects move around, depending on browser window size or resoluti

Hello from Sweden!

Im helping my mom and are creating a website for her. This is the first time i use Dreamweaver, before i have tried a little notepad HTML but not much. I have a problem i cant find a solution to and would be very happy if someone could help me.

I used one of the html templates included with Dreamweaver and then added some objects with the Draw AP Div tool. I was amazed over how easy it was! I didnt have to care about any
borders, i could just use this tool to add an image or a bit of text, anywhere on the website!

However, later i noticed that when i opened the site in firefox, the objects created with the Draw AP Div tool was completely out of portion... So my solution then was to move all the objects in dreamweaver out of portion so they would look nice in firefox instead..

I had a feeling that would not work long term, and i was right because all i need to do now is to resize my firefox window or change screen resolution for the objects to get out of "sync" with the website again..

So my question is - How can i use the Draw AP Div tool and make the objects independent of browser window size or screen resolution? So that they stick at the same place on the
website no matter what?

/Leo