Thanks very much for the video. It looks like Cyberlink calls these "Sketch Animations" in English, although sketch and draft are good synonyms
I've tried the steps in your videos on two different PCs with existing projects, and neither one shows more than a one second delay in returning the cursor.
What happens if you try placing that PiP in a new project, with no other timeline content? You can also type Ctrl+A to select all your current timeline content and delete it, then place the PiP object and see if the delay is still there or not. If it's there but not in a new project, maybe something about the current project is the cause. DON'T save those changes when you close PD, though!
Also, see if turning OpenCL on or off (Preferences | Hardware Acceleration) makes any difference, or if rebooting your computer and trying again does.
If nothing seems to make a difference, please share the DxDiag test results as described in the Read Me Before Posting
guide so we can see if anything jumps out.