Any support group that encourages identifying feelings and needs can benefit from the Heart-Canvas. A common way of learning compassionate communication is to join a "practice group", which is a group of people that meet with the purpose of learning skills while practicing compassionate communication. Here's an example of a practice group in Silicon Valley. Practice groups meet anywhere from once a week to once a month, and can be held online or in person. Practice groups may be found anywhere in the world through the Center for Nonviolent Communication website.
Usually, a practice group has something called a "check-in" or "empathy circle", where each person in the group gets to share what's going on for them while other people practice giving empathy. The Heart-Canvas can be helpful for the listener to identify feelings and needs, and then reflect these back to the speaker in the form of a question -- e.g. "Are you sad because you aren't connecting as much as you'd like?"
If a Heart-Canvas banner is available, the speaker is invited to walk on either banner to help identify their own feelings and needs (this is a form of self-empathy). Another use of the banner is to have the speaker share while sitting, and to have all listeners quietly place gems on the feelings or needs they're intuiting from the speaker. Then after finishing their share, the speaker reviews the feelings/needs to reflect on their resonance for them -- e.g. "that lands for me" or "...it's more like this..."