Hi Spacjamen,
sorry but I also disagree a little. I think shaprs great characteristic is its simplicity. If you need the full pack of functions blender is your choice. But for those who find most 3D apps way too complex Shapr should be kept as simple as possible. I do agree though that there are some functions missing. And I agree with the spline functionalities. For now my workaround is the following:
Draw the curves of your electric wire from one view (e.g. XY) and then draw a second curve from another (say YZ). Now give every curve a closed area and extrude the first and substract the second. This gives you a body with one edge that exacly matches the center line of your electric cable.
Now put a profile (some oval shape in your case) at the end of that edge and sweep it along that edge (yes you can sweep using an edge of a body not only a spline!). As you have done so the only thing left to do is deleting the body and your wire is finished.