There are several different versions of Skype and Skype for Business. Of course, since ChromaCam is a PC only app, you will need a Windows PC and not a Mac or other machine.
The basic summary is that ChromaCam works for nearly all instances of Skype and Skype for Business, including: Skype for Web, Skype for Desktop, and all variants of Skype for Business which are not based on Lync 2013 architecture. There are two fundamental types of Skype for Business, the first of which is bundled in various ways with Microsoft Office and Office 365. ChromaCam supports all of these different Skype for Business variants.
Then there is the Skype for Business app which is based on Lync 2013, and that Skype architecture is not supported by ChromaCam. The Skype for Business Web App is tied into Lync, and so it is not supported. The Windows 10 app, Skype Preview, is also similarly architected and not currently supported by ChromaCam.
If you have any of the supported versions of Skype, here is how to make ChromaCam work with each....
If you have Skype for Desktop, login to Skype and in the header click: Tools > Options > General > Video Settings > Select ChromaCam from the dropdown. And ChromaCam will start automatically whenever you place your next Skype Video Call!
ChromaCam works great with both the Skype Web App, but you will have to have the browser plugin installed in order to make a video call (and thus use ChromaCam). In the Skype Web App, you will need to first start a video call, and hit the white plus button on the bottom of the call screen. Then select "audio and video settings" and then select ChromaCam from the Camera dropdown selector.
Skype for Business Basic 2016 MSO and Skype for Business (For Office 365) both work beautifully with ChromaCam. In either instance you will go to: Tools > Options > Video Device > Select ChromaCam from the dropdown box. Once you're in a call, click the video camera icon and click "start my video," after which ChromaCam will startup.
Lastly, if you are using a Supported version of Skype for Business, when you are given a <join.microsoft.com/meet/user/abcxyx> URL, allow yourself to be taken to the meeting via the Skype for Business desktop app, if you'd like to use ChromaCam. If you "Join Using Skype for Business Web App instead" then you won't be able to use ChromaCam.