I am not familiar with your subject product but maybe you have to modify the path environment variable to add additional search paths. It could be that the setup tool for the product does not set the path variable or is only smart enough to set one component into the path environment variable.

Another thing to consider is that often the IDEs will configure the project with a few MAKE or NMAKE type scripts. Sometimes these build scripts contain local "path" type specifications that work like the system path environment variable. You may need to hand edit one of these build scripts to add an additional directory component to the script.

Since you say that you found two individual configurations that half work it could be informative to Diff the two configurations with a tool like BeyondCompare to spy into how the scripts between the two vary.

Michael Karas