I can't open it -- I'm on C3D 2012 and got a message that it was saved in a newer version -- sorry. Hopefully someone else can assist you.
I've had this issue before. I think it also involved an alignment which started with a curve. If you don't plan to have any station labels that are negative, change the label style to drop the sign.
I've also run into this problem on occasion. Seems to be an issue somehow with calculating the location of the reference point relative to end of the arc that starts the alignment. I found that setting the reference station to something just barely positive seems to work.