I have never done any serious film scanning (Iíve always sent mine out to a lab), so I have no experience of those problems (perhaps itís just as well).
There is a (possibly insignificant) update from Smith Labs, however, as the latest round of testing reaches a conclusion. No scans today though, I just donít have time.
* Testing shows that even at a small print size where LR reports a print resolution of 600 ppi, there is a definite gain to be had by resampling in LR to 720 ppi, and there is a visible and worthwhile improvement in fine detail in the print.
* This may be a contentious result, but never mind. My tests seem to show that it is best to avoid
print size resolutions with odd numbers like 351, 577 ppi etc. For example, 600 ppi resampled to 720 looks better under a loupe than 601 ppi resampled to 720. Subtle tonal transitions in the original file seem to be rendered more smoothly. However, it may be that my eyesight is just giving up with so much testing and too many late nights
PS In other words, if you have set up (like I did) for a printed image size of 12x9 ins and the resolution reported by LR is 601 or 603 or 597 or something, resize the cell very slightly to get 600 ppi instead, upsample to 720 and you will get a better print for a fractional difference in printed image size.
If you make use of the User Templates within the Lightroom Print Module, you can get all your favourite print and paper sizes set up with ideal resolutions (in and out) plus your profiles and everything else. It takes a while to sort it all out, but once itís done you never have to worry about it again.