setup microtic router for blocking unauthorized web access

we bought a microtic some months ago and the people who sold it were supposed to do the programming but recently I found out configuration is not according to our needs. Example: -- I set the microswitch to block all url containing facebook -- it works in case users put [login to view URL] in the commandline -- but if users put [login to view URL] they can open the facebook page anyhow so finally the filter is completely useless, for weeks i believed it worked correctly but recently found out users still can access restricted sites like facebook, hotmail, gmail and others loosing time and endangering our sistem. also I want to restrict downloads of any kind the idea is you give me a detailed info how to avoid that users can access (restricted) webs staring with https, at least it seem that current filter settings only apply to http sites, showing me how to modify this settings if necesary (pdf document with some screenshots should work) .. this has to happen without interrupting or slowing down our interernal system (access to vtiger, asterik pbx, other featurs) .. same applies to block all kind of downloads like mp3, movies, music, etc. find attached a sceenshot .. there you may see web proxy settings, and differente command lines/one opens url other is blocked as it should be find attached too stucture of our network, note that ... elastix / vtiger / asterik pbx is before microtic and with IP [login to view URL] ... pc and phones are after microtic and use IPs ranging from [login to view URL] potencially .. its important to maintain access to [login to view URL] from all internal devices