hey troubled , there are several ways to serve a summons namely registered post, by hand to parents , place of work etc.
however can you clarify where you heard there was four more coming ? if you paid a fine then you received a fine in the post then failed to pay hence court, the other way is the garda can issue a summons , if you have any questions in this area ill be glad to answer.
you can not loose your licence nor receive points or effect insurance as tax is a revenue based fine. no ancillary, mandatory or consequential orders can be made on your license