It's nothing to do with UEFA/non-UEFA, if it's outside the EU i.e. Turkey, Russia, Israel then they count against the quota of three non-EU players.
Obviously not, as it is regulated by the EC and its bodies. However, UEFA mostly tries to incorporate directives and regulations set by the EC (FIFA's (Blatter's) statement that would have limited the free movement of workers in violation of EU provisions on that matter was an exception)
As there is an agreement on partnership and co-operation between the EU and Russia which ensures that, according to employment law, Russian workers are entitled to exactly the same treatment as EU workers.
P.s. States such as Romania and Israel, all of which have partnership agreements with the EU, have also been included since 2003