I wouldn't be surprised if that topic was already mentioned here, but I didn't have p8 before so I didn't follow "p8 threads" till now.

My question is about the shortcuts in graph window (only when in graph window) - NONE of them works for me - I cannot even play animation with ENTER or advance frames using arrows (or keyframes using (shift)tab). Moreover frame indicator shows the same frame when I do change the frame (by mouse:) inside graph window.

Is there a solution for this anywhere?

The "play animation by enter" appears to be gone, which is a good thing
as far as I'm concerned.  This use of the Enter key in earlier versions was
a constant irritant, because Enter is more commonly used when typing a
parameter value, and the two functions would often interfere.  If this change
was intentional, I'm happy!

Advancing with arrows still works for me; the tab for keyframes works when
the graph window is selected (frame is blue.)

After your post I rechecked that and for me nothing works (just restarted p8 and still the same).

None of them is working while graph window is active (blue) - but when it's inactive then advancing with arrows and tab works perfectly. And even enter for playing animation is working there :)

On the topic of shortcuts in general, some of the most commonly used commands don't have a shortcut. One must go to the menu to Duplicate or Conform To, for example, and the Back and Bottom camera views are inexplicably missing shortcuts. This wouldn't be so bad if there was a way to add your own shortcuts. I hoped this would be fixed in P8, but alas.