Hi! I just got my Twiddler 2 days ago. I love the tutor (at the link below), it seems just right for my current abilities. The trouble is, it almost never goes on to show statistics after the last character is entered. Instead, after a while it starts flashing as if I hadn't completed the exercise.
http://twiddler.tekgear.com/tutor/twiddler.html
It showed statistics only once out of several tries. I'm not sure what was different that time, but it may have been the first use of the tutor after restarting my browser. The actual first time I tried the tutor, I loaded it, mucked about, then reloaded it to stop it flashing before actually starting. After that, I reloaded each time I wanted to start another attempt. Sometimes, I closed the tab, opened a new one later, and it still didn't complete. (I'm not not sure whether this was a proper new tab or 'reopen closed tabs,' but I think it was the former. I can't re-check now because my Twiddler has just stopped working altogether.)
Browser is Opera 52.0 on Win7 64-bit.