I had the same problem with Cubase LE 1.0.10. Everything installed correctly but Cubase just wouldn’t load it. It’s a pity as this version of Cubase is limited to 2 VST instruments and a multitimbral instrument like Model-E would be really useful.
Strangely enough Model-E seems to work OK in other DAWs which is ironic given that most of the legacy Steinberg instruments (jx16 for example) only work in Cubase. I know Model-E is unsupported but a fix/workaround for this instrument would be most welcome.