I have four cats, two kittens recently introduced, and had cats before I had cavaliers. One reason I initially was attracted to the breed was because they were said to be good with cats!
I'd first off whole heartedly recommend a companion for your kitten, whether male or female. Kittens are generally best homed in pairs -- they get along well generally and become very close if they know each other from kittenhood onwards. Sibling pairs are especially close. They needn't be an opposite sex pair (and keep in mind the need to neuter in a timely way if you have two of opposite sex -- they can be sexually mature at 4-6 months! Thus it can be much safer to take two of the same sex). As you guess, they also will have companionship and a playfriend for life. This can take a lot of pressure off the humans and a dog in the home. And I love how two affectionate cats interact -- grooming each other and sleeping and playing together. When I did cat rescue we always explained that kittens and the eventual adults cats are much easier to care for when in pairs.
People always assumed we were trying to home them faster but unlike puppies, which generally benefit far more from being homed as singletons, they truly are so much easier in pairs.
On the training -- the key thing is restraint and care, and going slow. This most likely means restraint for the dog, not the kitten. I have had dogs that were initially reactive to cats eventually just adapt and the best way to do this is initial short exposure, gradually building up to longer periods. The cat becomes boring when it is around all the time and no longer a novelty! I also give a firm 'no' or finger wag and stern look to barkers or chasers. I have an xpen that I will pop a chaser in for a time out as well. If the dog is getting overexcited, in it goes. I've three rescue cavaliers sitting on the sofa near cats right now that initially barked and chased the cats and could hardly be in the same room... sometimes I would put them in the pen and let the cats in. Gradually the excitability extinguished. Two of them will still sometimes give a half-hearted little chase but the cats now view it as part of the playfulness of the dogs and don't really care or even do much in response.
For dog safety, I would trim kitten/cat nails regularly to make sure they don't have really long sharp ends.
If Nalu is used to a cat in the home I doubt you will have any problems. All my cavaliers that grew up around cats are pretty ho-hum about the three new ones we have added as the oldies passed on. They seem to differentiate between 'their' cats and other cats -- ie cats in the house are 'their' cats. Each new addition is a new situation of course, and should be handled with caution, but almost always things should go fine.
Hope that helps!