It took me long enough to find time to post it, but here it is, the V2 crossbow improved on all aspects. It can use thick rubberbands as well, because it has two strings.
I won't explain all steps in detail, but in return I made clear pictures showing what to do in order.

The main thing about this crossbow is the trigger, which improves and replaces the old design.
This crossbow is not meant for 250+ feet ranges or something ridiculous, its shooting about 120 feet depending on how long the middle piece is. Power is alright, shoots easily through cardboard.

Pro's:

Very compact
Doesn't have exotic pieces/broken pieces
Lightweight
Very low amount of friction adds to arrow acceleration

Con's:

Reduced range/power due to being smaller

Step 1: Piece Count!

Starting with the 'fun'part, collecting pieces.

Counts in text because pictures seem a bit vague:

Small Wheels:-------------------4
Blue Spacers:--------------------22
Wide Spacers:-------------------18
Yellow Connectors:-------------65
Dark Grey Connectors:---------5
Green Connectors:--------------16
Red Rods:--------------------------22
Blue Rods:-------------------------36
White Rods:------------------------98
Light Grey Connectors:----------7
Blue Connectors:-----------------18
White Connectors:----------------16
Purple Connectors:---------------16
Red Connectors:------------------19
Yellow Rods:-----------------------12
Green Rods:------------------------122

Step 2: The Bow

Just follow the pictures.

Step 3: Middle Piece

The middle piece, often referred to as handle.

Step 4: The Trigger

Time for some hard stuff.

Step 5: Assembly

Yay you get to put it together!

Step 6: Finished!

Go and shoot some stuff! If not satisfied with the range, just make it longer ^^

I just keep recycling that ammo picture xd

PS: I'm gonna have a small war soon, see picture =d
PSS: Phone camera didn't do too bad =o