I only need the curtain, that is, the upper part because I have the lining. Do you sell just the top?

Only the snap-in liner can be removable, the outer curtain is the shower curtain like others, not just the upper part(mesh top). Hope this can help!

Does both the outside shower curtain and the inside liner snap on/off?

Hi, for this one "Hotel Style Cotton Shower Curtain with Snap-in Fabric Liner", it's included outside shower curtain and inside snap on/off fabric liner.

Is the liner shorter than the waffle weave curtain? If so how long is it? Dry quickly with mildew?

Hi, thanks for great questions. The snap-in liner size you can refer to the size chart above, a little shorter than curtain. It's water resistant and dry quickly.

The sizes listed on this page doesn't include the size : 71W x 72H. When will that size be available (in white)?

The size of 71W x 72H is the one of 72x72 as listed, since the exact width could be more than 71" but not to 72" and the dimension is measured manually with deviation about 0.2-0.5. Hope this can help.