You need the Liveload SCT software if it's an X2 not SCT device updater which is for X3 and later models
Link
http://www.sctflash.com/showdeviceupdates.php?PNID=9400&DTYPE=
You want the one that is 3rd down. LiveLoad software, download the .exe file and open it.
1) Open program, it will say Connect SCT X2
2) Plug X2 in, then click Browse to select your custom tune ( take it from your email and place it on your desktop, it should be a .cef file
3) Select 1,2,3 line on Liveload, the X2 can hold up to 3 custom tunes at once, make sure to rename them so can recognize difference between the 3. If just using one tune, just put it in Line 1
4) Click on Add button, this will load it on the X2
And far as checking to see if its unlocked or not, go to Device Info, scroll to bottom and see if it says Aftermarket, Stock, or Unused
Aftermarket = Locked
Unused = Unlocked
Stock = Half locked but can be fixed using the Liveload program
Trust that helps!