ECC Error Curve 256, 384 or 521

Ecc Sample test
I'm getting such an error.

It also gives random.dll error.

Curve : 256, 384 or 521 selected
text: test

Debugger Exception Notification
Project cryptoDemoDelphiFMX.exe raised exception class ECryptoPack with message 'Encryption algorithm not implemented'.
Break   Continue   Help  


We have only implemented signature algorithm for the p-256, p-384 and p-521 curves. 
RandomDLL.dll is our DLL to generate random integers for Win64 platform, you need to copy it in the C:\Windows\System32 folder if you are running a 64-bit Windows. 
Best regards,

I say it, it bursts when you select them.

p-256, p-384 and p-521 curves. 

Yes, it is normal because encryption is only available for ed22519 and ed511187 curves. 

So why is there combobox : 256, 384 or 521 in the demo project?

For the signature demo, below encryption demo.