First, you have to know "there is no engine in the market" allowing export App ready to use and publish on all platforms.
Always need specific resources in each market to create apps in their stores.
You can export in C2 for Windows 8 - 8.1. The result is a project almost pre- configured and pre-ready to go up to the store.
You can also export the project in HTML5 format. With XCode you create a project using the webkit and include your export created with C2. With some work you can uploading an App to Mac App Store.
Obviously you need to be registered as a developer of Microsoft and Apple and have minimum knowledge to access these markets.
You must consider that the main advantage C2 offers is not the final production in each of the markets. The main advantages ( for me) is the composition, WYSIWYG, scheduled routines and YOU SAVING TIME . If you value the total development time , C2 is your tool.
Again , once completed development will need certain knowledge and tools to carry on certain platforms , however it is available to everyone and not expensive .
Now you must consider:
- Platforms you want to port the game
- Windows 8 Market : Need PC with windows 8 - 8.1. Register as a developer
- Mac App Store: Need Mac . Register as a developer
- App Store: Need Mac or access PhoneGap or similar. Register as a developer.
- Nintendo Wii U: Register as developer and advisable WiiU Dev Hardware Kit.
Think that 98 % of the work to be applied to create an app for each market is in internet tutorials ( many in Scirra ).
About the Speed ??and 60fps, you can get them without problems (
if the platform supports) as long as you respect certain rules. That happens in all engines.