First, sorry if this has been already reported. I just notice the following behaviour:
ON+ENTER (simultaneously pressed) locks the calculator. On my model with the last version of the firmware batteries must be removed.
ON+F1 (simultaneously pressed)seems to reset the memories.
Entering a negative exponent for 10^x makes the '10^' symbol disappears from the upper lines after pressing enter.
As a comment, if I like the calculator for all the functions it provides I find the display quite poor compared with competition.
Hope the Prime will correct that with a lighted screen.
Regards