Installing Nuendo v11 options

1 I have Spectralayers Pro 7, I downloaded and installed with Nuendo v11, the Spectralayers ONE as at the time I thought it would open a window within Nuendo (does it?) It installed, but I cannot find it in my applications folder (Mac) . I cannot find it with a search. Did it install, or not? If not, that is fine, I just don’t need it taking up space.

2 What is Bloom? I cannot find any information on this.

3 I have numerous versions of Halion (Halion Sonic Factory, SE artist, SE basic, SE Hybrid, Sonic SE Pro) is there a description of them all somewhere to tell me what they all are and which app installed which? Very confusing, presumably all sounds are available in Halion?

4 Why in Wavelab does some audio files show I can edit in Nuendo, and others are greyed out so I cannot edit back in Nuendo (when it came from there a few moments ago)?

Thank you