Shouldn't number 1 be:
 C:\Usr\Proj\ThreadSearch\.bin\Debug\
That's not all, there is something wrong with these variables.
- Create two new console projects (test 1 and test2) in a workspace
 - add "cmd /c $(TARGET_OUTPUT_FILE)" to both in pre-build steps
 - activate first project
 - try "build workspace"
 
For both projects you will see "./test1".  

It seems to me, that the variable expansion works only for the currently activatet project.