I've started using FlexMonkey to run some tests, and for the most part I have it working well.
One area that I cant get right is entering data into editable datagrids - I've tried using the recorder, as well as coding it myself with no luck.
Just trying on these forums on the chance that I find the right person who can point me in the right direction! Unfortunately, the FlexMonkey forums are pretty useless.
It's been a while since I've used FM, but an issue we ran into with DGs in general is uniquely identifying rows. I think we ended up using custom item renderers with a hand-crafted automation id to help FM find the right renderer. In general, 90% of our FM problems were automation id collisions (i.e., FM sees two display objects with the same automation id and doesn't know which one to simulate interactions with). We have a number of components that craft their own custom automation ids.