I was modifying old setups lately, by directly editing them with Orca. It’s not such a great experience, but I really didn’t want to go through Dark for such simple modifications.
In the process, I found that one of the worst parts of the format is decoding the Type column in the CustomAction table. Because of that, I have coded a very simple application that tells me which options are selected when I input the number in the column. I hope you find it useful, it’s uploaded here: http://www.codeproject.com/KB/install/customactiondecoder.aspx