This bug still exists but more of a visual bug/inconsistency.
When zip and Aes 256 is selected:
Click pae on. Encryption greyes out but remains at whatever you set it while greyed out.
When you click it off it ungreyes but it’s now disabled.
When 7zip and Aes 256 is selected:
Click Pae and the encryption turns to “Disabled” and greyes out.
When you unclick PAE it ungreyes but remains as disabled.
When BH and “BH Encryption” is selected:
Click PAE and now BH encryption is greyed out.
Unclick PAE and BH encryption stayes greyed out, but if in fact you go forward to create the archive the encryption is on (asks for a password).
Take care :P
Mame