I have this exact same error, but my situation is slightly different...
I just installed LV2014 (32 bits) (for any reason, only the 32 bits version was available on the DVD I just received).
I'm running Scilab 5.4.0 and installed the latest version of the gateway I found on the NI website (http://sine.ni.com/nips/cds/view/p/lang/fr/nid/210055)
I installed the 32 bits version of the gateway and I get the 1046 error code when trying to run a simplistic scilab script.
Can LV 32 bits and Scilab 64 bits interoperate or is this the reason for this error to be returned ?
I checked the registry and the SCIPATH matches the place where scilab is actually installed.
Regards
Gerald