An update on this, from am email from Pearson support:
1. Go to the "Start Menu" of your computer.
2. Access "Control Panel".
3. Click on "Flash Player".
4. Go to the "Advanced" tab.
5. Click on "Trusted Site Locations".
6. Add the drive letter where Tout Le Monde is accessed. (e.g. D:/ or D:\)
In our case, I added the drive letter 'H:\' of the mapped drive that TLM was running from, and it started working again.
If you use Chrome rather than IE you need to use the 'Global Security Settings Panel' at https://www.macromedia.com/support/documentation/en/flashplayer/help/settings_manager04.html
click edit locations, add, then the drive letter same as above.
Still a pain, because this needs doing on every PC that will use TLM! I couldn't find a solution to distribute these settings.
