i guess the deal with giving you a bunch of products that you can't use without purchasing is the best way that they have to distribute upgrades without requiring huge downloads.  basically "here, this is our entire product line, if you want to unlock it just buy the key from us--you already have the files."  just ignore it--get the stuff that you paid for to work right?

so, ignore EZdrummer.  S2.0 should work all on it's own.

also, on my initial installation which i purchased approximately a week after it was available, i didn't have to download anything--you may be imagining that it's a download because it's copying an a$$load of data from a DVD--forget your typical software installation from a CD, this is literally an a$$load of files from a full-on DVD.  yes, i did the full install with mic bleed and the hole bit.

i don't know if it matters whether you get the latest version first or not.  my experience was with buying the original dvd, installing it then upgrading as the new releases came out.  there certainly shouldn't be any issues with doing it this way as opposed to having the latest update first--unless, of course, you are on Snow Leopard and Toontracks has special instructions for Snow Leopard.  i'm still on Tiger so I can't help you with OS issues--except that i did install Solo on my wife's Leopard macbook without issues.

so, my installation of S2.0 basically gave me:

Solo: works great as a standalone drum module for when i don't want to open my DAW to play some drums--the stupid thing is that the file-types for the kits is different from S2.0 which makes absolutely no sense to me.  you have to set up a Solo kit AND a plugin kit just to get the same kit standalone?  weird.  the good news is that the kits are sooo sweet that it's worth a little extra effort.

S2.0 (AKA Superior Drummer) plugin (i believe both AU and VST versions installled--Garageband doesn't seem to recognize it so i can't verify the AU part): to me the primary reason for buying the box--i have drum pads so i was looking for an upgrade to my crappy Yamaha dtxpress brain sounds (man, what an upgrade to my crappy Yamaha dtxpress brain sounds!.)  it should work as a standard VSTi (Virtual Studio Technology Instrument).

EZplayer pro: this is the loop player that should be used to drive an S2.0 track.  i have to be honest with you, i've only opened this once or twice before tonight just to see what it does.  it seems to be a sort of proprietary midi loop player but, because it doesn't link up with the DAW that it's in to follow Play, Stop, Rewind and other position related commands (to my knowledge anyway) it's more of a glorified browser for the included loops--i just figured out that you can drag and drop the loops into your actual DAW tracks and go from there which is much more useful than having a separate player.  to do this i guess you just drag one of the variations to an instrument track (one with S2.0 waiting to do it's dirty work preferably) then copy, cut, paste, loop etc. to build yourself a drum track.  i don't know exactly how many "grooves" installed--if you drill down to all of the variations there seem to be quite a pile of them.  i believe that i download the MirZ stuff but i don't know that it's showing up in the browser--usually that just means that you have to teach the browser where they have been installed--i notice that the Menu drop-down has an Add Path function.  i will take a look and clue you in if i find anything. 

i'm sorry if it seems that i've downplayed the coolness of EZplayer and the loops--if you don't have pads they seem like a good place to start--i especially appreciate the fact that you can separate the grooves down to the individual kit pieces allowing you to mix and match as you please.  with the new knowledge that these can be brought into your DAW as MIDI which opens them up to editing is pretty sweet indeed.

also--you may be thinking that this whole computer DAW thing is just way too much for you, admittedly you bit off quite a chunk with Superior.  hang in there, this is definitely not typical of most VST installations--the good news is that S2.0 is in a pretty lofty class of plugin instruments so it's worth a little learning curve.