I think what Dave is referring to is the neat little tube that allows you to fill the spirit cup from a hole in the top of the frame. Without these it can be fiddly to get access. & no - no flames come up the tube!
The priming tube on the 535 is excellent - it doubles as a funnel but is also lined with a strip of wick which gives the pilot light similar to the gizmo Chuch describes.
The tube Dave mentions can be seen on one of the pics on this page
http://www.spiritburner.com/collection_optimus181.htm