I'm afraid I'm totally stuck.
THe download comes as a .tar not a .zip. so This isn't recognised for local update within the phone.
So, trying to use the flashtool, again, the TAZ file, not a zip, which I can extract using winzip, but the resulting folder does no contain a suitable target file for the Scatter Loading .
I am sure that given the length of time that has elapsed that you have solved this issue, but if not here is what I have done after experiencing some glitchy issues with my BV7000 (Android 7). I downloaded the latest ROM via the links provided by admin on this forum, followed all the instructions, even tried the multiport flashing tool, all tried with absolutely no success. I couldn't get windows 7(64bit) to see the VCOM driver for the M6737T chipset, then when I thought I had it sorted, I ran the flashing tool and almost bricked my device, I then ended up using Platform-Tools > Fastboot recovery via command line to rescue my device from the mess it was stuck in.
Anyway, for the last few weeks, I have been in this circle of not getting it sorted and then happened across your post on here. This gave me an idea, why not download and unpack the ROM file t728y-jk-bv7000-63-fhd-128g16g-bom13-N_BV7000_Blackview_20170612-sign_user
extract it using 7-Zip as it is a .TAR file and then repack it with WINZIP as a ZIP file and then transfer it to my SD Card and perform a local update.
Opening Local Update on my handset, the device is able to recognise the now zipped file and it is ready to update, it gives me all the warnings about loss of data if not backed up etc etc, but it is ready to install, using this method.So converting it this way works and avoids the pitfalls of the flashing via the SP flash tool. If you haven't got Winzip, it is available on a 21-day free-to-try basis, You will need to put the ROM file on your desktop prior to zipping it up as the file name is to long for it to be placed in another folder, such as My Documents or Downloads.Before install, I need to look and see if this is latest ROM or if there is a newer one for my BV7000, as well as determining if this is going to produce some unwanted side effects...though I may have to click the button <Install Now> to discover all of that.