I've had the same type trouble with a different screen capture app. It worked with the action button for awhile, then didn't, then did, etc. I'm always trying new apps, tweaking, and while my changing set of apps seems to affect some things, like button use for screen capture, the
timed screen capture option has worked consistently. Okay, so it ends up giving me a ton of screen shots, but among them is the one(s) I want. Mission accomplished.
This app is free, available here:
http://www.zionproduct.com/products.html
Still, I hope somebody can provide a fix to use Touch button for screen capture.