The upstairs room solution is pretty obvious go vertically up through the wall in the computer room into the attic space run the cables to where they need to go then drop then down into the rooms punch them into the back of a wall plate done.
Cable drop through attic multistories.
There s a 2x4 at the top of the wall with vertical 2x4 studs.
To drill through a rug make a small cut in the rug with a utility knife and then drill down through the cut.
Install coaxial cable cable tv or satellite tv cables concealed in wall spaces from non living spaces above or below.
By using a drill bit sized large enough for the cable.
I have run the odd cable in my house wood frame wallboard by drilling down from the attic into the hollow wall.
Use a piece of string that you can add a small weight to such as a steel nut or whatever you can find.
For single floor homes with a basement the basement may be the best path.
Drill holes in the floors as per your markings by using a power drill equipped with a 5 8 inch drill bit.
Step 4 drop the coaxial cable through the holes in the floor until it reaches the connection in the basement.
These methods will work for any cable telephone network thermostat power etc.