We have had several authors experience problems with their pdf files when using our LaTeX document class, with the top margin being "cut off" relative to where it should be. We know that it sometimes happens to users of later versions of MiKTeX on a PC, and it can also happen to users on a unix or linux system where the default setting for the dvips and dvipdf utilities has not been changed from A4 paper to letter size paper.
If you are using a linux or unix system, please try reprocessing your document as follows:
latex yourfile
dvips -t letter yourfile.dvi
ps2pdf yourfile.ps
That is, use dvips and ps2pdf (so do manually the 2 steps dvipdf combines) and add the "-t letter" option to dvips. This should resolve the issue.
If you are using MiKTeX or some other utility to process your LaTeX source, or if the above did not work, we would be very grateful if you could share with us the following information: operating system you are using (Windows, Mac OS, Linux, etc); utility you use to process LaTeX source files (e.g., MiKTeX with version number, PCTeX, a LaTeX distribution for Mac, etc); and utility you use to create the pdf file and how you do that (e.g., in WinEdt, using a utility like dvipdf, etc). We would also be grateful if you would be willing to share your LaTeX source file (.tex) and the .dvi file created by your LaTeX processing utility with us. We may be able to diagnose the issue with this information.
We can begin the review process with the version of the paper with the top margin "cut off" so as not to delay things; however, if we can correct this problem, we would be able to send the corrected version forward to the process.