I've installed the tools in exactly this manner on eight different machines. Following the instructions *exactly* will make flowdumper work.
When you say "it doesn't complain," are you talking about the line that says "no library found for -libnls"? If so, did you make exactly the edit in the article, or did you use the patch in the posted followup comment?
I can't comment on the patch in the comment, but I can say that the edit in the article has always worked, both for me and a variety of other people. I have lost no functionality from the tools, on 4.x and 5.x.