Halion 4 not listed among VST'S


after working around the installation process for halion 4 (mac), it is not listed among my vst’s when i open a instrument track but it is in my applications folder.

as far as im aware, the installation was successful.
the product is registered.

please help.

has no one had any problems installing halion 4 on a mac then?

im running cubase 4 on leopard 10.5.8 could this be the problem?

if so, will lead to another problem, cubase 4 does not run on snow leopard (apparently)