From the Readme_First.pdf file:
I do not know why that happens. It happens outside of EFILive_Explorer's control. :( If I ever figure it out I'll fix it.While FlashScan's firmware is being programmed a "percentage complete" counter will be displayed from 0% to 100%. Sometimes that counter may "freeze", however the reprogramming process will continue. It should be complete in less than 20 seconds. A dialog box indicating success will be displayed when the programming is complete.
Regardless, if FlashScan boots normally (not into dead poll) then you can be sure that a firmware update was successful. FlashScan has built in CRC checks similar to the GM ECMs which will gaurantee that the data programmed into FlashScan is 100% correct.
If even just 1 bit of 1 byte is wrong, FlashScan will boot into dead poll forcing you to retry the firmware update.
Regards
Paul