I reviewed the file you're having difficulty with. It's a binary STL file which has some fairly strict requirements. You can read more about the format here:
http://en.wikipedia.org/wiki/STL_(file_ ... Binary_STL
Essentially, there is a header and then a 32-bit integer that specifies the number of triangles in the STL file. The problem with your particular file is that the number specified in the header does not match the number of triangles in the remainder of the binary file. Creator responds correctly and warns you about the issue since it would otherwise fail upon importing.
Being that it's a binary STL file, there isn't much more information I can gather from it. So 2 ideas to help us troubleshoot this.
1) Can you try exporting a much simpler file from TurboCad? A simple cube with 6 faces should be modeled with 12 triangles, so that should help narrow where the problem is.
2) Is there a way to export the STL file from TurboCad as ASCII instead of Binary? If it was ASCII, I would be able to help much more in actually seeing what is going wrong with the file.