After some searching around, it appears that the only way to scroll in Lunacy is to either have a mousewheel or drag while holding down the shift-key. It would be nice to have a hand tool so I can drag on my surface tablet without needing a mouse or a keyboard.
Basically, Lunacy supports all the touchpad actions your driver supports. Please try to hold the spacebar and move the pointer, it should work also if you’re using the touchpad. As for the double-finger scroll, please check if scrolling left and right in the same way works for you on this devise outside of the Lunacy app.
Another way is to click your mousewheel (click not scroll) and move the canvas. Just in case - there are scrollbars on the side and bottom or the workspace: