My laptop model is Inspiron 17R 5720 and Im having the exact same problem after the Microsoft Cumulative Update for Windows 10 Version 1607: August 31, 2016 - KB3176938, done Sep 4th. I was also already running Win10 and it didnt mess with Webcam Central - till yesterday when I gave the reboot necessary to install the update files.
Pan/Zoom/Position Arrows show as available to be used but if you try to use then, nothing happens and back to full zoom. Only thing it allows me to do is to change to Face Tracking.
I called Dell Suport Center and for about 2 hours I ran diagnostics and tried possible solutions with the tech assistant but he wasnt very helpfull at all. All diagnostics came back with positive/OK/passed results and they offered me a paid support to fix the problem. Not exactly a good solution, is it?
It was clear though MS updates messed up with the webcam driver - I checked myself at Devices/Imaging there was an update for the driver done exactly when MS updates were done. Unfortunatelly, the rollback option wasnt available.
For that matter, I decided to uninstall the whole Windows KB3176938 and CAPICOM (what ever that is) updates done using Control Panel/Updates but no-go. Next step was to google for that problem which leaded me to other Dell Forum threads pointing to reinstall Webcam Central which also didnt work at all then I bumped into your thread which is about the exact same problem of mine.
I must say I'm quite shocked NOBODY else posted a line here and NOBODY FROM DELL gave any attention to it yet. I can only hope with my post it might drag more attention and the proper reply from Dell.
If it still wont work I shall try a restore point before MS updates and if the problem persists I will seriously consider to rollback to Windows 7 to give it a try. I don't think paying for support to see if they can fix it or to buy an external webcam are fair solutions at all.
Does anyone from Dell or any members have the same problem, suggestions, contributions or solutions for this issue? Thanks in advance.