Maybe, maybe not.

No beta SDK Support! Kobold2D generally doesn't support Apple iOS SDK beta or Mac OS X SDK beta builds. Any incompatibilities will not get looked at until Apple has released a GM Seed or final version of the latest SDK.

Kobold2D is somewhat at the mercy of other libraries. For example, cocos2d-iphone also fixes incompatibilities only after the new SDK has been officially released.

General Tips About Apple's Beta SDKs

Do not talk about beta SDKs! Rule #1: Do not talk about Apple beta SDKs! Rule #2: Do not talk about Apple beta SDKs!

There's a reason for that: beta SDKs are under NDA (non-disclosure). You are not allowed to publicly talk about beta SDKs. Once you allow users to discuss issues that appear due to Apple's beta SDKs the likelihood that someone mentions something that is under NDA is high. Similarly support is hard and sometimes impossible if you can't mention the very thing that you need to talk about to explain a possible solution.

Always install beta SDKs separately! If you have to work with a beta SDK, make sure that you install it to a different directory and not /Developer. You might want to suffix the /Developer folder with the version number of the beta SDK, for example /Developer51 if you're installing the preview version of iOS SDK 5.1. You can then switch between the latest official SDK and the beta SDK by running the tools (eg Xcode) from the corresponding folder.

Do you really need the beta SDK? Unless you must develop at the bleeding edge, you should prefer to wait for the public release of the new SDK. You generally don't get support for beta SDKs anywhere but the closed Apple Developer forums, and help for particular libraries and compatibility issues with them is minimal at best. Only consider installing a beta SDK if: you have to use one of the new features in your App. you have to test your App very early for compatibility issues, for example because you want your app to be among the first to support a new Apple device. you are generally curious and know the risks, know how to install the beta SDK to a separate folder, know how to distinguish between official and beta SDK tools such as Xcode, won't ask questions about the beta version in public. In any other case it is better to wait for the new SDK to be officially released.