That was one of the delays, I actually tested about 1000 games over a period of a month, taking snapshots as I went.
Some games have multiple snapshots, I tried to take a snapshot of the in-game play and another of the title screen.
Anyway, the snapshot code got a good work out.
Yes, it was a bit of an effort, but at the same time I quite enjoyed it as I got to play games I would not usually play.
One particular game Zwackery was awesome to get going for the first time!
Of course not every thing works out, during the course of development when I add and update game drivers, only 85% or so actually work as sometimes I run into problems that I cannot solve or the version of MAME does not support. I now look for these issues before starting to add a new game or update one.
One of the biggest bugs I found was discovered literally a few hours before release! That was the 'sound' bug and fixing that, I've found the same games sound really awesome now - crisp and clear - the way it should.
Again Zwackery was in this category. I played it on the GCW-Zero and my PC and the sound is of course perfect and on my A320 it sounded crap. Quite a few other games suffered from this and when I found the issue it was a like halleleujah! Found it! And I couldn't wait to try a whole lot of games... again!
There are a few I still want to add, Sega's Enduro Racer is on my list but it will require a big effort of replacing all the system16/18 games which isn't trivial.