...yeah.
first, just in case no one's posted this, the secret level was part of the Mazz VI contest. Every Mazz map had a contest for who could beat the map first, except Mazz VI had sort of a double contest, where it was who could beat all 5 difficulty settings, and THEN who could beat all 5 difficulty settings on the secret level. So I guess it was sort of a ten-tuple contest. So anyway, you can read about the contest, and the trick to getting started on the secret level right
here.
speaking of which, the teams that won these contests were generally led by players who had already beaten at least the last three mazzes on legendary (not to mention accomplished mythers in their own right). and each of the last few mazzes added a few more new elements than the last one. heck, I had beaten every Mazz since Mazz 1, and even I remember playing mazz 6 for the first time and being like wtf is that floating eyeball shooting laser beams? wait what just happened to my dwarves? the hell did those tornadoes come from, and what does this special do? W T F?!?!? dragons!?! so yeah, from the perspective of a total myth noob, i imagine you really have quite a daunting task in front of you.
my only recommendation would be that you get the myth down first, and then the mazz. once you've got the controls down, you can work on recognizing the billion and one different specials there are in mazz.
there's probably no better place to start than the myth singleplayer campaign (for the myth TFL campaign, DL the Fallen Levels plugin, that I think frum linked earlier).
it's really a well put-together solo game, so all of it's pretty good (I prefer tfl, but apples and oranges, you know), but the Mazz-like solo levels would be Shadow of the Mountain from TFL, Across the Gjol TFL, The Great Library from SB (SB=myth2), aaand maybe the Wall from SB. there might be others but it's been a long time, I don't really remember.
finally, as for the film pack, i started looking into films and i got really into it, so I've been going through my film archive since January 2007, and I'm putting together the best of the best. I'm up to mid-april, so I should be done soon. It'll be good, I promise!