the functional properties of a textile art item depends on the actual item. firstly the function of a textile art is to look good and express your theme/concept/message in a creative way. if your textile art is something that is wearable, construction features could be important (depending on end-use and how often the wearer would wear it), so its functions would include fit, and comfort. If its non-wearable (like a wall hanging) you would probably have to find some other functional properties.
btw- in textiles i MAKE THINGS UP. and it works because im gettin 90%'s. so take my advice... and bullshit your way through it
there is a very helpful website which discusses the questions for the folio. (if u dont already know about it). i use it for all of my assessments. its hsc online
http://hsc.csu.edu.au/textiles_design/
im seriously so far behind in my mtp. im doing an evening dress in the focus area of apparel inspired by indian textiles and 1940's design. im getting very frustrated!! haha and i havent started my folio.
hope i helped you. sorry if i confused you :S lol