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.
http://www.mediafire.com/download/kz8klq5jzs8n859/Blu+Studio+5.5+Stock+ROM.rar
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.
https://www.youtube.com/watch?v=qnJr7RQa2Kk
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.
http://www.blogtechtips.com/2015/03...phone-flash-tool-to-flash-any-blu-smartphone/
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.
*EDIT*
http://blog.catsinja.com/2016/08/blu-studio-5-5-de-brick-general-flashing/
Information that fixed the issue was located in the link below.