Thanks for your response. A friend ended up helping me with fixes/workarounds on this, and the site is now okay, but here were the problems.
1. Re auto-cropping, here is what she said:
There's a function called "the_post_thumbnail" that pulls a thumbnail based on what it thinks is the best fit. Since the twentyten theme has already obligingly generated a 940x198 image, it picks that. You can explicitly tell the function what image you want it to pick, though--it's in header.php. I made the following change (line 77):
2. The second problem had to do with the three featured text boxes. On the production site, the Featured Text fields would not accept HTML. I had to include all my text for these areas in the Featured Header Text fields.
As I said before, the development site had no problems with this, and had also moved from the Twenty-Ten theme to Adamos. WP, the theme and all plugins were up-to-date on both. However, the development site had fewer previous themes than the production site, so maybe that had something to do with it.
Thanks again for your quick response!