As you have read in the tutorial for the e-mail content part you can create your own redirection to individual success and error pages.
The example in the tutorial was:
IH|redirect|0||10,100|http://www.apple.com|0
IH|redirect_error|0||10,100|http://www.microsoft.com|0
To create your own redirection, read the following steps.
Create an new structure level, name it e.g. hidden, set this structure level to hidden, visible and public. This level needs no alias. (see Fig.1)
In this strukture level you now create 2 new levels, the first one you call success, the second one error. Here you should also define aliases e.g. success and error. Also set them to hidden, visible and public.
Now your stucture levels for this area should be looking like this:
Now go to the article section and create an article in each of you newly created structure levels: success and error.