LR4 is taking longer and longer to import from my flash cards, 1.5hrs and still counting on a 16GB. It is also sometimes crashing my whole computer on export, particulary export to iphoto. There have also been some issues exporting to photoshop - it won't take any LR edits, only crop?
Sounds like a bunch of issues, not just one issue.
For slow import from flash cards, check the hardware (is the card reader failing? or USB connection failing?)
Computer crashes are often memory problems, or video driver problems.
Problem exporting to photoshop? I don't have photoshop so I can't help with that but this is a common problem here in the forums, you might want to search on that issue
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