This happened to me once when I used Hammer 3.5 with an old version of Zoner Hl compiling tools. They worked fine with Hammer 3.4 so I figured I had to update to a newer version, and it worked!!
It was a long time ago... maybe before I was registered, I think I updated to ZHLT 2.5.1 but now there is 3.4 so it's better to use it.