we've tried a few things (including .save all)

Like this worked here, just get the operation point annotation from the menu and descend into the subcell

Hmm, one thing to keep in mind is that the op simulation only computes the initial operating point. Your VDD comes from a pwl that is 0 initially so the op will only give you 0 answers then

Annotation from a transient simulation is also possible. • In the go to Simulation -> Graphs and make sure that 'Live annotate probes with b cursor' is selected. • Add a graph from that same menu and place it somewhere in your schematic. • Load your transient simulation data. • Double click on the graph area to open the trace configuration window • Double click on one of the trace names to add it to the graph. You can select colors at the bottom. • Since you have more simulations stored in the .raw file, you may need to select the simulation type you want to plot things for in the trace configuration window (you can also remove the op simulation from the script) • Once you have one or more traces in the graph, close the trace configuration window. • Hover your mouse over the plot area. Hit 'f' to auto-scale the horizontal axis, and hover above the vertical axis, hit 'f' again to auto-scale the vertical axis. • Hover your mouse above the plot and hit 'b' to add the cursor, you can drag the cursor with your mouse to get to an interesting point in the graph. The saved values at that point in the simulation should now also be annotated into the graph

Here's the modified example, also now saving the gm and id of the transistors

If you're still missing things, check that 'View -> show/hide -> show hidden texts' is enabled

I just checked it and the 2 key things I was missing was the 'b' key and the show hidden texts

that's so useful!