I have made a lot of adapters for hose connections from pvc water pipe. Find a diameter of pipe that is slightly smaller inside than the outside of the connector on the tool. Heat the end of the pvc pipe till it is flexible, then jam it on the connector. Let it cool and it will fit perfectly. You can do the same on the other end of the pvc for the connection to the hose, using one of the fittings that came with it.
For connecting the vacuum to the saw, I used a power strip connected to a foot switch. I plug the vac and the saw into the strip, and when I step on the switch, both draw power from the strip. Both will start and stop at the same time.
Tom