Upgrading from Profesional to Platinum only 328 MB ??

I took the offer for upgrading and I'm now at a location with good internet bandwidth so I can proceed. 
Because I need to use the offline method I'm not using the Command Centre. 
On my Products page is Sonar Platinum Foxboro "upgrade"  and the file is only 328 MB. 
This seems way too small? I don't want to return home just to find out this was one of those download installers and it proceeds to download 5 Gigs at home where I pay $5 a Gig. 
 
The big question is-- as an upgrade, does it overwrite Professional? I have no problem with that  I just want to make sure I downloadall the correct parts while I have good internet to work with. 
 
I also am still having issues with the Dim Pro registration number. I have only ever installed it once to my DAW and the serial number on my product page when inserted say's " invalid registration code" It doesn't seem to matter as it still works but it's a PITA to always have the splash screen pop up on projects using Dim Pro. 

I think I see how it works, the old versions of Sonar was 5 Gigs or so  but that because all the additional content . I see that the list below the core program is each a seperat download so this now makes some sort of sense.
The price you pay for not using the CCC I guess. I have to download a dozen or more items.. but the good part of this is I don't need half of that stuff so I like the abillity to choose what I want. 
 
Using the list it would be cool if there was a pop up balloon with a breif overview of what each item was about. I have no clue what some of these items are without reading the promo web page. 

SONAR Platinum uses 19 installers (not including DPro and Rapture). I was trying to identify the parts unique to Platinum when upgrading from Professional.

Thanks,
I'm downloading most of it right now. I'll download all of it if there's time. 
Using CCC would be the better method, but for me this is an excellent alternitive. 
I have CCC on my DAW and I can hook up the internet, so after I manually install everything, I'll runn CCC and see if all the green lights come on. 
Mostly I have no use for loops and pre sets, that sort of stuff. I'm exited about drum replacer. I just joined a new band and look forward to recording real drums again in the near future. I always replaced the kick drum in the past so hope the new tool works better than audio snap did. 

Good to know,, I have yet to open it since March. See no reason, but I thought I might just to double check if all was up to date. 
Seems you should be able to install manualy and then run CCC..  Is it that dumb that it would attempt to download everything again?? That's would be a bummer for me.
So I guess I'll just not even bother with it.  Will be installing everything this morning now I'm back home again,,, and it's raining here today. Playing at an outdoor wedding tonight and they are calling for thunderstorms!