Hi,
The above are not supported without potentially digging into the UE4 source and implementing these yourself.
The apex cloth and destructibles are available in the engine. Though it is worth noting that the destructibles are handled on the CPU and not the GPU. This is because Epic wants to develop features that are available for all its users. Nvidia higher end effects will only work specifically with their GPUs which would alienate other those using non-Nvidia cards.
The SDK provides source for building these with Visual Studio and implementing into the engine.
The physx lab, as you pointed out, is just a stand alone interface for creating destructibles. Alternatively you can download the plugins provided for 3ds Max and Maya.
The goal with UE4 is to provide development tools that everyone can use and not just a fraction of the community. We don’t want to exclude one GPU from features of another. This, again, goes back to the destructibles and why they are handled on the CPU rather than the GPU.
Thank you!
Tim