Maybe I'm missing something simple, but I can't get back to Sender Station after going to Anachronox after the hive thing.

When I go to the tours area, I can't buy a ticket because I need to take the shuttle. When I get to the shuttle on platform two, I can click on it, but no option appears for me to go anywhere.

You don't need to - you have your private shuttle waiting for you on the second {third?} floor of the Platform Area.

platform 1 is empty

platform 2 has a big ship standing (where I can click on, and get some text about it but no options appear)
looking like this:
[IMG]http://i42.tinypic.com/ecxad.jpg[/IMG]

platform 3 there is only the standard taxi thing waiting. It does not give any options to leave anachronox.

platform 4 is the entrance-level

Yeah, that's Dr. Bowman's shuttle. Where in the story are you right now?

I just came back from the hive, I accepted the quest for bowman, but I decided to go to anachronox first, I have grumpos and Democratus in my party

I think I figured out what went wrong; I went to anachronox using the anachronox shuttle, ending up at anachronox tours. I think somehow that messed up the travel system.

I reloaded an old save and used bowmans shuttle, now I can actually get back on it.

*sigh* have to redo the caves and the junkyard again :/

Thank you very much! :)
I was having exactly the same problem.

Wow! Thank you, guys! Same problem, solved)))

I'd call it a "bug" or - better - a lack of gameplay testing. The game shouldn't let the player use Gate 4 on Sender Station to go get back to Anachronox, because once you get there you can't use the Rho's shuttle neither buy a ticket back to Sender Station.

Funny thing is they actually created dialogs for it (Stiletto wondering "This is not Rho's shuttle...")