As my 3rd post in this forum I'll provide clarification on a documentation issue in the Home Designer Pro 2016 Reference Manual with the hope it will save someone else some time finding the correct answer.
On page 30 under "Using A TrackPad" it states "In OS X 10.10 (Yosemite), use the click-hold gesture to pan; in 10.9 (Mavericks) and prior, click-hold and two finger panning are supported." Mention of panning using trackpad on Mac wasn't included in the 2015 version of the docs but I think they may have added it to the 2016 docs based on a phone call I placed to support 1.5 years ago on this very issue.
Regarding helping to clarify the docs, I'm not sure on the "click-hold gesture to pan" or "click-hold and two finger panning" in prior Mac OS versions, but, I can state that such approaches don't work with the current Mac OS version, i.e. El Capitan.
To pan in Home Designer Pro 2016 Mac in El Capitan using a trackpad (and I imagine in other CA products although I haven't tested) one needs to hold down the command key while performing a 3 fingered drag on the trackpad.
As this took me a while to figure out via trial and error I hope someone else benefits from this info.
Bill
P.S. There's some mention of this issue at https://chieftalk.chiefarchitect.com/index.php?/topic/5321-two-finger-panning-busted-in-pro/ as reported by another user although it's unclear what version of the Mac OS he was using when experiencing the broken functionality of two fingered panning.