Just to make it clear, I am not using any module anymore that uses omxplayer.
For me MMM-RTSPStream stopped to work for my install and use a while ago (reason unknown) and for MMM-Dreambox I do not have place on my screen (but a nice module nevertheless).
I have kept my MagicMirror pretty simple and static, just 5 modules and a video stream from my outdoor IP-camera.
No fancy things with rotating, voice commands, gesture commands, etc.
Everything that really matters in one view.
As an alternative for MMM-RTSPStream, I just use pm2 for my video stream.
The omxplayer is an overlay in all uses anyway, so I just ‘overlay’ it on top of the MM modules.
I left space on the left side of the MagicMirror by only using top and bottom positions.
pm2 controls the processes, like with MM (I enabled it using the same commands for MM, except that I used axis iso mm).
That being said, I can try activating MMM-RTSPStream again to be able support a bit.
pi@MagicPi:~ $ pwd
/home/pi
pi@MagicPi:~ $ cat axis.sh
#!/bin/bash
echo "Starting Axis stream ..."
# No rotation
#omxplayer --avdict rtsp_transport:tcp --live --video_queue 4 --fps 30 --win "0 625 590 957" rtsp://axisviewer:Trosknurt12@192.168.178.56/axis-media/media.amp?resolution=640x360
# Rotate to match custom.css rotation
# 640x360 == --win 'x1 y1 x2 y2' == "600 300 960 940" == x2 - x1 & y2 - y1
omxplayer --avdict rtsp_transport:tcp --orientation 270 --live --video_queue 4 --fps 30 --win "600 300 960 940" rtsp://user:password@192.168.178.56/axis-media/media.amp?resolution=640x360
pi@MagicPi:~ $ pm2 list
┌──────────┬────┬─────────┬──────┬───────┬────────┬─────────┬────────┬─────┬────────────┬──────┬──────────┐
│ App name │ id │ version │ mode │ pid │ status │ restart │ uptime │ cpu │ mem │ user │ watching │
├──────────┼────┼─────────┼──────┼───────┼────────┼─────────┼────────┼─────┼────────────┼──────┼──────────┤
│ axis │ 1 │ 2.5.0 │ fork │ 11127 │ online │ 1066 │ 2h │ 0% │ 220.0 KB │ pi │ disabled │
│ mm │ 0 │ 2.5.0 │ fork │ 4658 │ online │ 41 │ 14D │ 0% │ 12.0 KB │ pi │ disabled │