vzw replacment touch pro wont flash

[ll31@ck]

Ok,so i got a replacement TP and when i put it in bootloader mode it was already unlocked.So i went 2 flash mighty's rom and it stays @ 0%.So i proceeded 2 try 2 flash silence,juicy,and a few others,no luck.Finally i tried flashing original stock rom and it flashed fine.Can ne 1 tell me if theres something im doing wrong or y i cant flash custom roms.Thanks n advance.