No. 2 has two uses, the top of a gas cylinder for a barbecue or for a caravan and the top of a buoy for use with divers. It comes in different colours.
No. 15 is some piece of clothing, I think, which goes on the klicky's leg, probably a knight.
Here's No. 24:
http://playmodb.org/cgi-bin/showpart.pl?partnum=30-23-7850Cheng is right about No. 30 - the early nozzles for the firemen's hoses. What a good piece of horizontal thinking, cheng, to use them as telescopes.
No. 27 is a handle of some sort and No. 28 is a window for the Steck wall which comes with the DS house and barn.
No. 31 is the top of the jack from the 3781 fire engine and the 3761 mobile crane.
No. 33 ia an internal divider wall for System-X.
No. 46 is a warning sign off a child's bicycle.
No.40 is an equipment tray which first appeared with the early, small fire engine.
In the second picture, the two small red pieces towards the centre are, I think, from the white water boat and fit on the top and take ropes.
No. 42 is a window from the 3965 family house.
No.48 is a curtain from the 3965 family house.
I recognise No. 43 because I've got one but don't know what it is.