I've got the speed camera database loaded now, although I haven't tested it for real (lockdown and all that) but it seems to show the destination flag at the locations, rather than the icons. I assume that is because they are loaded as destinations, but when I just loaded the test data yesterday it showed the locations as a pin similar to Google Maps, which is probably preferable. Is that what you get, or have I done something wrong?
When you change your proforma and icons the unit can remember the old ones. A reboot, long press on the on / off can fix that. That's an issue in the units firmware. I've seen that occur. I would recommend a reboot and see whether the icon changes after. If not import them again.
Picking off the icons and then saving to the destination menu doesn't effect the icons shown.
As far as testing the sound you can put the unit into demo mode which I covered at the end of the text. You place the car at a location close to the point then pick a destination that takes it past the point.
This text from the instructions:
To test the upload, a simulated drive can be taken by using the advanced menu of the infotainment unit. Put the unit into demo mode. Enter the cars location close to a safety camera by street address, then navigate a route that goes through it. You should hear the warbles if you have toggled them on. You can check the warning distance or leave it for a real drive. Demo mode can be toggled back off again.