Yes, can operate in fastboot but adb is hit and miss, due to the nature of adb and windows 7 and driver conflicts, but essentially i can access fastboot and adb. Fastboot is basically saying that anything I attempt has worked, when in fact it hasn't.
I've tried your suggestion of flashing cwm - literally - 100 times. No dice. Same for twrp. Fastboot gives a 'success' message for anything I try to flash, but when I then reboot i'm still in twrp 2.5.
I appreciate your willingness to help but the bottom line is I've gone beyond everything you're suggesting because I've tried those things and had no luck, which is why I'm kinda resigned to exchanging the thing, but exchange will run into issues when they reboot it back at the warehouse and get stuck in a twrp bootloop.