Hmm, do you think they would make a big deal in Hong Kong if the backpack was used as my laptop case (to count as my personal item)? It very much resembles a carrying case except it has the shoulder straps?

I wouldn't normally ask such a weird question but HK seems really strict after what you said and after viewing the website.

For my 1 carry on item, I measured my carry on bag and its height is EXACTLY 22 inches tall from the floor to the top when sitting on the ground and ok on the other dimensions since depth is 7 inches and width is 13 inches.

I see they have a special measuring bin that you have to put the bag in the make sure its within the dimensions so thats why I worry. I hope it isn't really 21.5 inches or something making my bag not fit in the event it was measured. I did some more mock packing and can now get my weight within 15 pounds using this carry on bag.

I really do appreciate all the advice so far. I believe that many of my fellow classmates also traveling aren't taking the CX rules seriously and do not know about how strict HK is. I also found many of the rules hard to believe at first.

They seem to think its only written and not actually enforced (eg the weight)