Yamaha DTXpress/DTXplorer/DTXtreme

Hi Guys...  
I appreciated your response to my last question... This seems to be a 
very helpfull & knowledgeable group... I must say again I am total 
newbie to e-drums... I love em and find them utterly fascinating...  
Ok to the point here... 

I need a tutorial in .syx files... I've noticed a bunch of them 
listed in the files section of this group... I am assuming that these 
files are custom drum kits created by the many smarter than me 
drummers in this group that can be loaded into the DTXpress user drum 
kit area...  

What software do I need to install on my computer to download and use 
these files ??

Will I be able to use this same software to store my custom drum kits 
on my computer ??  

How do I get the info from my computer to my DTXpress II brain and 
visa-versa ??  (just direct me to the manual section)

As always guys, I totally appreciate your time...

Dennis.....