As it is illegal in many countries to use GPS maps that have speed camera locations built in, can anyone confirm before I install these maps if speed camera locations are built into the maps - in particular UK and France.
The underlying OSM map will likely have speed cameras mapped in all developed countries. Nothing is done to stop people mapping anything, although I presume that anyone trying to map certain sorts of outlaw businesses that sell certain illegal products (generally where it is illegal to possess, and there is no legitimate market) and services might have to have their edits removed. I haven’t heard of that happening. Such businesses probably would not want to be on a map easily available to the police, anyway.
However, I think you are actually using a map, exported by a third party tool, onto a third party device. It is probably best to ask the supplier of the tool or service that does this, but, in any case, unless we know what that tool is, people can only guess and say what they know about their guess. There may well be an option on the tool that creates the working map to suppress objects that the consuming device would otherwise interpret as speed cameras.
Speed camera coverage will be erratic, as it will depend on whether there was a mapper in the area that wanted to map them. People may have mapped speed cameras in a way that is not recognised by the tool and device you are using.