Just a quick update on the NW.js/greenworks situation:
I've been testing NW.js 0.13.0-alpha4 (and alpha5 is already out, looks like their release cycle is finally speeding up). It's based on Chrome 45 (46 now with alpha5 I think) and the jank issue looks to be finally fixed - every frame comes within 0.1ms of v-sync on my Windows dev machine running sbperftest. However there have been some backwards-incompatible changes going from NW.js 0.12 to 0.13, and changes to the Construct 2 build are necessary for it to export. So the next beta should come with an official NW.js 0.13-alpha5 (or newer) support, but you'll need that beta or newer to export with it. Either that release or the next I'll review Greenworks integration, and hopefully be able to ship it in the C2 editor at last.
Just to review why this has taken so long in case some of you weren't aware: NW.js has been on a slower release cycle than Chrome for a while, generally releasing only once every few months. Chrome 38 had a bug that basically broke v-sync scheduling and made everything janky. Google eventually fixed it a couple of versions later, but NW.js got their next update in just before the fix, so it's been affected by the bug for a lot longer than Chrome. Then on top of that their 0.13 release has involved significantly reworking how the architecture works, which has meant a longer development time than usual.
The good news: NW.js is nearly there with the 0.13 release, and the release cycle seems to be speeding up again (they've mentioned on the email list about how they have made big improvements to the build system and reduced build times a lot). Although the next update will require a new version of C2, we've still had NW.js updates separated from C2 for a while now, so we can update them independently and avoid the problem with earlier builds where you could end up stuck with a broken version. And once Greenworks is integrated that should make Steam publishing a bit easier. The next update will be a huge jump in the Chrome version - from 0.10.5 to 0.13 covers Chrome 35 to Chrome 46, with tons of bug fixes, performance improvements, and new or improved features (including better WebRTC compatibility). So hopefully things will be a lot better from the next build onwards.