Denis, that looks about right. It will make more sense when you actually rig it up. Here's one thing you could change to save you some string. The way you have the tack line rigged up it's 2-1 back to the halyard. But on a small spinnaker of a Nacra 5.2 (as opposed to say an Inter 20) you really don't need 2-1 for the tack line. All you have to do is tie a block to the end of the tack line and run the halyard through that, making sure your tack line will pull the spin tack to the end of the pole before the block hits the front beam.

I sail a F16 Blade single handed most of the time and I have found the single biggest problem is friction in the spinnaker up and down system. Anything you can do to eliminate excess line and friction in the haylyard/tack line system will help you set and snuff it much faster with less chance of a snag when it's halfway up or down.

I like my spin. halyard clete up on the mast so I can pull the spin up hand over hand, using my weight to help pull, rather than pulling straight back from the beam using arm strength alone. But to do that you can't run the -single line- setup you have pictured. You have to run a separate tack line. Personally I like the two line system better as there is much less friction in the halyard so I can raise and lower the spin faster with less pulls.