Currently this program only supports graphs of the type 'histogram', but it will eventually support the other graph types mentioned.
You need to enter your data into the boxes on separate lines, separated by a ';'. So for instance you could enter:
23;
12;
10;
11;
12;
20
Notice that the last line of data does not have a ';' after it. Also note that you need to have as many labels as data points, or you can expect weird results. You can view some sample information here.
You can use many different colours (complete list available here). The first colour is the bottom of the bars, which fades into the next colour at the top of the bars. The next two colours are a similar colour gradient for the background of the graph.