AErender app to render specific rqindex items

Trying to get aerender to render different items in the render queue.  For example, if there are 20 items, I'd like for once instance to render 1-5, one to render 6-10, and so forth.  However, Can't seem to get it to work.  This is what I'm doing:

/aerender -project /project -rqindex 1-2

Error I'm getting is:

rqindex 2num 13

aerender ReferenceError: Object is invalid