To set new connectivity to a feature (e.g. Gas Fitting):

1. Click on the Connect Features tool.
2. Left-Click on a feature (e.g. Gas Fitting) to select it. The feature highlights and all features directly connected to the feature highlight.
3. Left-Click on a nearby feature to select it for inclusion with the first feature's connectivity. The feature highlights.
4. Continue selecting features as in step 3. Each selected feature highlights in turn. Each subsequent click also accepts the previous feature.
5. Left-Click in empty space to accept the final feature to be connected.
6. Right-click (Reset) to complete the operation.