Indirect Draw For Particle System In DX12

I'm working on a GPU based particle system in DX12. Each frame I run a compute shader that updates all the particles and appends the indices of the active particles into an index buffer. When it's time to render, I use this index buffer as a lookup table so that each particle can find its own data.

Atleast that's the plan. The problem is that I don't know how I should handle the indirect drawing. As I see it, I currently face 2 problems:

1. If I use the UAV counter from the index buffer, then I …