Force antlet to boot from CD?

I created a Windows 10 antlet but I want it to boot from a virtual CD.  It did once, but now it won't.  Is there a way to force it to boot from the CD?  Perhaps edit the XML definition file (where is this anyway?)

Hi chrisdavis:

Yes, you just need to add the Virtual CD (by path or import) under Virtual Drives in your antlet.

Please note that this will remove the file if you are using by path.

I usually make copy before adding virtual cd or disk.