Loarder.sin error

I have an Xperia play (R800i) running AuroraPlay v2.0.0 and most likely some version of doomkernel (they were on the phone when I received it) and I'm trying to change to a kernel and rom that suit my needs better, but my phone is erroring out in flasher. I'm new to custom phone software so I was wondering if anyone had an idea on whats going wrong? the flasher error is Loarder.sin finished with errors. Thanks in advanced