Sorry... I didn't notice when you posted this.
Well, the "complicated" description I had posted before, was for the purpose of being able to use the D8B with the computer, but also with the HDR (as long as the computer is on).
If HUI isn't working, then let's just work on troubleshooting that part of the setup, first.
For troubleshooting:
1. Connect the MIDI Out of the D8B directly to a MIDI input on your Yamaha MIDI interface
2. Connect the MIDI In of the D8B directly to a MIDI Output on your Yamaha MIDI interface
3. Set the D8B to HUI mode
3a. Press the "General" button on the D8B
3b. Press the right arrow key below the display twice until you see "HUI"
3c. Press the 3rd "Select" button to open the HUI menu
3d. Press either the 1st or 2nd "Select" button to toggle HUI mode on or off
4. From the Logic Pro X menu, go to Control Surfaces->Setup
5. Click "New", then "Install"
6. Select "Mackie Designs - HUI", then click "Add", then close the device list.
7. Select the HUI picture, if it isn't already
8. In the upper left, choose the MIDI Inputs and MIDI outputs the D8B is connected to
9. Close the Window and go back to the arrangement window and load a song.
Faders 17-24 should now control the channels in your song, and the transport controls should work.
Is this working now?
If yes, then we could tackle next, how the HDR could be added to the setup, so D8B, HDR and Logic on your computer all work together. The "complicated" setup I was describing before, was supposed to make all of that work at the same time. But let's just try it simple, with only the HUI connected, for a moment.
Best of luck!