Copy a Tornado BSP that uses the same CPU as the one you want to test. For example:

% cd installDir/target/config 
% cp -r mv1604 mv1604_Tool

Go to your newly created BSP directory and edit the makefile. Change the line "TOOL=gnu" to "TOOL=Tool". Also invert the order of the following two lines:

% include $(TGT_DIR)/h/make/make.$(CPU)$(TOOL)  
% include $(TGT_DIR)/h/make/defs.$(WIND_HOST_TYPE)

This allows the toolchain-specific build macros to override all other default definitions. Then go into the BSP directory and type make release. This builds several images, depending on the BSP. It usually builds:

vxWorks		standard vxWorks image
vxWorks.st		vxWorks with built-in symbol table
bootrom.hex		bootrom
bsp2prj		project facility image

Once everything is working, test it from the project facility. Try creating "downloadable application" projects for your toolchain and building them. Try creating a "system image" project from a BSP that uses GNU as the default toolchain. From the "build view", create a "new build" and create the build by using your new toolchain. Verify that image builds.