cannot get my dyson back together.. help?

i took it apart,, cleaned it all, waited a week for it to dry. Now for hours I have tried to get it together, I cannot get the balck rod that opens the bottom cannister in the slot and I cannot get the perspex cannister off the blue bit so the blue bottom opens so I can fix it from the bottom. Maybe I have to put it all together and when it is full up unscrew it all!!

Any clues anyone> thanks, Amanda