@bertnl - a number of things have to be set to record and see IVS events on the playback timeline
1-
On the NVR set the Schedule and make sure you have both Regular and IVS shown for each day (*also do same on snapshot for IVS and Motion only)
View attachment 75934 View attachment 75936 View attachment 75935
2-
On the NVR Set to Record like this
View attachment 75937
3-
On the Camera set Smart Plan for IVS (light bulb highlighted)
View attachment 75940
4-
On the Camera make sure the "record" box is ticked for your IVS rule
View attachment 75946
5-
Now on the NVR PLAYBACK tab you should see colored hash marks for IVS events as well as the green full-time recording
(showing examples from both the new 4.0 dark UI as well as the older "light" colored UI)
View attachment 75943 View attachment 75944
*Note use the slider at bottom right to zoom into the timeline