Bug. User keyboard ineffectice on certain keys

[towe]

Hey there.
I haven't found anything regarding this via the search function so I made this thread.
I'm new here. German automotive engineering student, swapped to the Prime from a CP330 today.

I've made a program that assigns all greek lower- and uppercase letters to their respective layers on the user keyboard, because the [CHAR] menu is rather clumsy.
Now, I've found that the [A B/C] is completely irresponsive to usage of its assigned user keyboard, acting like no action was assigned.
It does, however, work flawlessly within the Notes menu.
The same thing occurs when attempting to use the [Enter] key.
Is this intentional? If so, why would it be?
It occurs on the Prime, the Virtual Calculator *and* the Android app, so this is definitely not an error with my device.
I'm running 2015.0617 on all of them.

Best regards, Tobias