Not much.
http://canapin.com/construct/worms/v8/
Damage calculation has some glitches (with the 2nd weapon), players can't move and some badly optimized events cause too much CPU work.
Plus, I didn't implemented the proportional particle effect.
Actually I'm refactoring my engine from A to Z because it was a complete mess. I'll create a thread about it when I have something to show.
My project is creating a multiplayer game inspirated mostly by Gunbound, which had an incredibly amazing gameplay until the developper ruined it. I could talk about it for hours.
That said, I've never finished any project, with Construct 2 or not. But I enjoy trying year after year <img src="{SMILIES_PATH}/icon_e_biggrin.gif" alt=":D" title="Very Happy">