After I had several customers ask me how to make roll drops, I compiled some advise from members of the Community Green Room (some of our Austrailian friends are extremely helpful!) and some internet instructions to offer this guide on construction of roll drops (also called oleo or olio drops). 

 

How to make roll drops:   http://www.studio-productions-inc.com/white_papers/wp_oleo_olio_rolldrop.html - http://www.studio-productions-inc.com/white_papers/wp_oleo_olio_rolldrop.html   Keep in mind that this is a good faith effort to record the common practices.

 

This article is pretty general although my customers are using it for Chameleon scrim, it would work for other non-stretchy materials.  If you are interested in using the Chameleon scrim material it can be printed as a complete false proscesium or for use on the roll drop as painted scenery and the cost is less than people think.  A recent example of a false proscenium drop we made for a customer to look like an old fashioned juke box is one that I'll send pictures of to you privately.  We were able to contain the cost by some careful layout.

 

The article should answer your question, but I'll repeat it. 'Yes' it rolls back up--although not spring loaded or anything.  A stage hand pulls the rope to roll it back up.

 

Besides the article, you can find the original conversations about roll drops by searching for Roll, Oleo and Olio on this forum.