Hi Felix, Pipe2 from 2008 should be working ok with v3, I just verified by getting it from the post here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=1463.48

I put it on the v3 beta Apr-16-2012 version (Windows), and then for example running pipe2 with the attached line (file pipe2_1.3dm) selected:



Generates this result with these settings (file pipe2_2.3dm):



I guess I'll need to get more information from you about your system to try and figure out why it does not work for you.

Can you please let me know which operating system you are using, what is your locale setting, and also can you please post a 3DM file with your input curve in it just to make sure it's not some kind of issue with the size of your line or something like that.

- Michael