i'm having the identical issues as y'all w/ Remote/ATV, but i think the culprit is the ATV update, not the app. whereas the app works flawlessly on everything else (and i believe in this situation as well), the ATV has been rife w/ bugs, overlaid menus on screens when backing out, and a few other issues. i've restarted it about 2-3x weekly for the last month or so, generally due to the overlaid screens.
re: the Remote app, it needs to receive a signal from the ATV that it requires text input, and then the app shows the keyboard. i believe it's the buggy ATV that's not sending the signal. one of the reasons i say this is also b/c most of the bug issues i've seen occurred when using the back button, and when begininng a session w/ the ATV and app it does open the keyboard at first, but once i start browsing around that's when it glitches and it won't show again.
i HEART Remote!! i think it's the ATV, just my 2¢. either way, i would still like them to fix, please.