Hi,
First, let me thank you for your excellent slides. Personally, I found the paper relatively opaque, and your slides help to unblock it. Just a few points. Firstly, you appear to have omitted the section discussing the Intermediate-good Monopolist's Problem. This may be done on purpose, but, since the equilibrium condition is simply the optimal choice on how to allocate resources between (intermediate) production and research, the governing optimisation conditions for the monopolist are relatively important, I think. Also, the equilibrium condition you state, i.e.
n_t = \psi(n_t+1)
is correct, but it is probably important to include that, by construction, \psi is a monotonically decreasing function on the positive reals, which is crucial for your statement regarding the link between current and future innovation to hold.
But these are minor points, thanks again,
the_pianist