We have purchased several Group series 310/500 series room system with skype interop licence. The issue we have is that when we screen share in a skype meeting, the shared content shaws as a video feed rather than content. This is an issue because if there are multiple people in the meeting, the contant shows as a small window like the other camers feeds. I have checked that the second input is set to content in the settings.
i think it´s normal. When you send content, Groups "kill" the videostream and send their content in the videostream. It´s not possible to send video- and contentstream in parallel. The Group doesn´t "transcode" the content sent from HDMI or App and puts it into an additional content stream.
The Group Series sends content over the HDMI cable as if it were a camera. The only way you are going to get good quality and have the content show full screen is to join the meeting from your laptop and share content with Skype for Business. We disconnected the cable from all of ours because of this.
Another thing we noticed before we discontinued using the cable was that when people in another location saw the content in a small box on their screen, they would lock the video spotlight on the content so they would see it full screen. When they did that, the Group Series sending content would show its video stream on the screen. In other words, the PowerPoint would disapear and the speaker would see themself on the screen. You can imagine how that would have a bad effect on the meeting.