iMac (Retina 5K, 27-inch, 2017)
High Sierra 10.13
Logic Pro X 10.3.2
24 GB Memory
 
I used Cakewalk Command Centre to install Rapture Session and the 5 sessions
 
The AU plugin is in the correct folder and it can be inserted in a Logic channel strip. Playing a MIDI file through it results in the keys on the keyboard strip of Rapture Session highlighting but no matter what sound I choose from the Factory Library, (this is the only visible library), there is no sound from Rapture Session. The window in the plugin says "loading xxxxx" when I select a sound.
 
Any help would be wonderful.
 
edit: added Solved - sc

Addition to my previous post....
So I gave up trying to get Rapture Session to work. Rapture Pro is on offer currently. I must be mad but I bought it. Using Command Centre I have managed to install Rapture Pro, D-Pro Part 1, D-Pro Part 2, Rapture Classic, Atmosphere and Guitar and Bass. They appear to work - I now have sound! I did this using "Install All". Command Centre tried to load "Keys" and crashed. I restarted it but I cannot select "Keys" or any of the products after that. They have a red graphic indicating that they are not installed. 
I'm beginning to get just a mite annoyed with this whole Rapture thing.
 
Any advice would be appreciated.

The Command Center is not necessary. The installers should be available in your account. The Command Center is handy for the RP program itself because it activates the program. The rest of the installers do not need activation.

OK - thanks for that info. 

I have, at least in my case, fixed the "no sound" problem in Rapture Pro.
 
I play in a band and we use minimal backing tracks - mostly drums and the odd guitar. I was trying to get RP to work using one of these tracks. At the start of the track were the 3 MIDI commands to change program;
Bank MSB,
Bank LSB,
Program Change.
Other plugin instruments just ignore these commands - EXS24, Kontakt, etc. I'm no expert with this kind of thing but if RP receives these commands it goes silent. There's no doubt a rational explanation for this which is beyond my limited MIDI knowledge. 
 
Anyhow, I'm now enjoying RP and it no doubt will be very useful in musical endeavours other than pre-made backing.

Cakewalk sfz engine synths do not react well to NRPN data. Removing this data is the best solution. Cakewalk DAWs have the ability to tell plug-ins to ignore this data.