More likely the problem it has is due to the omitted /CIDSet in the font descriptor.
The error is in the display engine, not the text extractor (since cut&paste work ok). And that means the problem is almost certainly not the cmap. The only other non-trivial difference I saw in the old vs. new pdf was that no longer present /CIDSet.
Unf., generating one in the text editor is bit beyond me-on-the-could mode, so I can not be certain of that although it seems likely (I checked with FF that the two glyphs are indeed in the embedded font subset and in the exact slots the pdf says they have, so that is also unlikely to be the problem.)
I’m not familiar with the internals of pdf files. When i use firefox as pdf viewer, the font information seems to go void in the new version (fun1.pdf).
