I would start by looking at @AdamV 's device Handler for the popp controller that I mentioned up thread. It has many of the same features and the original device was also intended to use the central scene command set, just like this one, so I expect there will be a lot of code you could reuse even though that exact device handler won’t work.
You can also ask for help in the developers section of the forum. Lots of people there will be glad to assist. 
Thanks @JDRoberts! Very helpful. My biggest concern was having the double and triple presses work with Rule Machine, but if RM supports up to 20 buttons per device, it looks like there will be several options. The number of use cases for these keep growing in my mind. Single press for patio lights, double press to include pathway lights, triple to include flood lights…
I received the switches yesterday and had a little time to put together an initiall device handler for the On/Off switch.
Here is the beta: HomeSeer HS-WS100+ Device Handler
Thanks to @JDRoberts, I had some of the prep code for the central scene notification in before I even received the switches. Since I was already specifically logging the sceneNumber and keyAttributes for the scene notifications, it was a simple matter to determine the values for all of the states. The DH handles both tap-2 and tap-3 for both the up and down cases, as well as the hold-up and hold-down cases. It also receives and handles a scene notification for a normal press up and press down.
The device handler adds a total of 6 buttons to handle all the tap 2/3 and hold-up/down cases. I put in virtual buttons for all the possible press states for testing. Maybe they’ll also come in handy for operational use?
Please let me know of any issues so far. Any and all suggestions or updates welcome.
Interestingly, the HomeSeer WS100+ looks and feels almost identical to the GE 12722, except for a lighter blue LED and lack of an air-gap switch on the WS100+. The WS100+ also has the same (annoying for some) short delay before the physical relay responds after a press.
I put together tables showing the button mappings, central scene notification parameters, and some comparison images with the GE 12722 at: http://darwinsden.com/homeseer100plus/
Great work! We should give a shout to @AdamV for his excellent work on the first community device handler to expose central scene commands.
Oh man, you beat me to it. 
Should have checked this thread before I put something together. My device handler is in my github (https://github.com/erocm123/SmartThingsPublic/tree/master/devicetypes/erocm123/homeseer-hs-wd100-dimmer-switch.src) if anyone is interested, but it isn’t as tested/polished as @Darwin 's. It has the button handling code from the Remotec button device handler I created a little while ago.
Hey, no problem! I only looked at the WS100+ on/off switch and haven’t even installed the WD100+ dimmer yet. Looks like we’ve even agreed on which buttons to use, so anyone can change between handlers without even needing to update their RM rules. That’s awesome.
Now that I know that the dimmer is in good hands, I’ll look at it another day. Heading to the patio. It’s five o’clock somewhere!
Oops, I didn’t notice that you were posting info for the HS-WS100+. Honestly, I didn’t even know about that switch.
So yeah, looks like we are working on two different (but related) switches. Works for me.
There’s an on/off master switch (WS100+), a dimmer switch (WD100+) and a non RF auxiliary switch (WA100+).
See link up thread for the full line.
Anybody try the HS-PA100+, that’s one of the plugs. I’m interested as they list support for 1800 watts. I own a hot yoga studio where we use electric space heaters during the winter to quickly pump up the heat. So far they have tripped every smart plug I have tried. The Smartthings plugs report a 1500+ wattage draw when on…before tripping.
I put together a WD100+ Dimmer Device Handler that includes the virtual tap 2/3 and hold buttons from the WS100+ device handler - since it took only a few minutes to paste that code in from the WS100+ into the stock dimmer.
I also quickly tried @erocm1231’s WD100+ DH and it appeared to work fine for me. Definitely use his if you don’t want all the clutter from the virtual buttons. I’m not sure how useful the virtual buttons will be for most people anyway,
Does this device support secure inclusion?
With the new device type does it support instant status?
Is the new device type needed for instant status?
I’m not seeing a 0x98 in the raw description for these switches, so based on my understanding, they do not support secure inclusion.
I can’t speak for @erocm1231, but yes, the device handlers I put together for the WD100+ dimmer and WS100+ on/off switch do handle instant on/off status via central scene notification. Right now, you’ll need these or other custom device handlers. The stock ST Z-Wave device handlers do not handle it right now.
Yes, the device type I created does support instant status.
Honestly, I do not know why z-wave devices are still being made without secure inclusion. Aeon is the only manufacturer that I know of that seems to be focused on this. It seems like all of their Gen 5 products (multisensor, siren, bulb, door sensor, etc.) support it.
IMO: I’m sure it’s part of the zwave standard. Their whole basis is around interoperability. Allowing manufacturers to create devices that wouldn’t support older controllers would go against this mantra.
Has anyone seen an issue with the HomeSeer WS100+ switch where after an on press (or hold-on), it toggles on as requested, then off, then back on again? I’ll call it “thrashing” for lack of a better word. I’ve seen this happen now with the default Z-Wave switch device handler and now also with this custom DH. It will happen consistently for awhile, but after giving it a break and trying again later, I can’t seem to get the issue to trigger again. Until the next time it happens…
So I’ve been scouring the forums and have not been able to find a definitive answer to what I suspect is a very simple solution. I have installed the HS-WD100+ (which I love btw) and am using Darwin’s device handler. How do I associate the double and triple tap buttons with actions (e.g., turning on dimmer as well as desk light, setting all room lights to 25% for movie watching, etc…)? Is that possible using RuleMachine or another smart app that I’m missing?
Thanks in advance for answering my noobie questions!
BTW, I paired one of the HS-WD100+ with a HS-WA100 and while the dimmer works, I could not get the companion switch working. Called Homeseer and they are sending me out another one incase the first was defective. If anyone has gotten the companion switch working, I would appreciate any insight you may have, as I am wondering if I did something wrong. Thanks!
The double, triple, and hold functions for each of the up/down cases are mapped to device buttons 1-6 (mapping here). Both my handler and @erocm1231’s use the same mappings. In Rule Machine, you can trigger actions using capability Button, selecting the appropriate button #, and choose “pushed” for the button pushed or held section.
And I knew I was missing something simple. Thank you! I’ll have to wait until I get home later to test and see if it is responsive.
I also found a good “scene controller” smart app by @Bravenel that I’ll test later. I’ll see which is more consistently reliable.
BTW, did you get any of the companion switches and if so, were you able to get them working?
I tested my WD100+ dimmer with a GE 3-way add-on switch and it worked fine for me, although I can’t recommend that anyone use a non-“blessed” configuration like this. 3-way switch wiring can be pretty confusing. Have you seen the Automated 3-way Switches: What should my wiring look like? (US Version) thread?