We have support for touchpads and multi-finger gestures like two-finger zoom. Unfortunately Dreamler doesn't support the two-finger tap for the right click. Without right-clicking you wont be able to bring up the Modelling Tool and create and link Activities.
If you are a PC user, use the right button under or above your touchpad.
If you are a Mac user and you use default OS X settings, you might experience that you can't right click in Dreamler. In order to change this go to the System Settings. Here choose Trackpad settings.
Your Secondary click will probably be set to Click or tap with two fingers. You should choose the following option here: Click in bottom right corner.
Your changed setting should look as the following screenshot:
You can now create new elements in Dreamler by click and hold on the bottom right of your touchpad and dragging an other finger over the touchpad to choose an option from the Modelling Tool.