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.
I was having the same problem. Here is a general solution:
Go to the TOOLSPACE tab and go to SETTINGS
Find youe station label by opening the ALIGNMENT---LABELSTYLES---LABELSETS---STATION---MA
Right click on the type of style and select EDIT (this will open your "Label Style Composer")
Click on the LAYOUT tab and find the CONTENTS property and select the corresponding prompt box in the "Values" column'
This will open another box "Text Component Editor". Select STATIONVALUE under the "Property" dropdown
Next, find the "Sign" row and select the corresponding dropdown in the "Values" column
Scroll down and select DROPSIGN
Finally CLICK THE APPLY ARROW at top of the "Text Component Editor" box.
Click OK and APPLY and the major station text format should be edited.
Alignment properties>>> station control, set it to 0
it probably got gripped and got squirly