I think that the most important think that you must understand in developing webapp using unigui (extjs) is the 'layouts', here a basic screen shots to give you an overview how to start with.
If I want that my mainform looks like this:
project from here: http://3msoft.net/mhmd/layouts_1.rar
I don't think that this is impossible or hard to achieve such design, if you look closely you could divide the dashboard to:
Keep in mind this:
if the parent layout is 'vbox' then for the children set width: '100%' if the parent layout is 'hbox' then for the children set height: '100%' flex: means the percent of width/height (depending in parent layout, if parent layout is 'vbox' then flex means height else means width flex=1 it will take the entire width/height unless there is another child with flex value <> 0 flex=1 for more than one child means all children will have the same percentage of width/height flex=1 for two, means first one will take 50% and second will take 50% flex=1 for three, means first,second, 3d will take 33% of with/height flex=0 the width/height will be the same as in design view