OK. So the reason for the double posting is to also bring up the thread. Basically the files I got here didn't work. I'm going to give a quick overview of what I did and provide more details later on. Along with a little bit of my own theories.
I think the D610a may have different versions. The ROM in the earlier post may work for some, but it didn't work for me at all. I ended up doing some searches and found another ROM elsewhere which worked for me. There were also some issues with the version of SP Flash Tool and I had to use the version provided from another forum (GSM Arena I think) which lead to this download.
That's what worked for me. It comes with SP Flash Tool version 5.1436.0 - the required scatter file and other files. Once loaded everything worked. The only thing is it left me with invalid IMEI. This was fixed by following instructions here.
Which involved sending commands to the phone and rebooting. "AT +EGMR=1,7,”new-imei”” for SIM1 and "AT +EGMR=1,10,”new-imei”” for SIM2 I think it was.
As for the whole button presses when flashing - that didn't work in my case. Once I connected the phone it automatically started the download.
There was also a matter of the correct drivers.
The link above has a lot of helpful stuff including the drivers. You need the MTK VCOM driver.
After that it worked fine.
Hopefully the additional info provided helps others.
Information that fixed the issue was located in the link below.