chaiusa - the LDC wordlist is actually an English-to-Chinese file, so you'll need to switch to that mode to use it. The flashcard crash and search crash both sound like they're memory-related; how much free storage memory is there on your Palm?
zig2101, same goes - we didn't make any changes at all to the PlecoDict database system between Beta 3 and 1.0, so it's very likely that this is related to some change in your system's configuration, most likely a reduction in the available memory.
The extra 1.2 MB of storage space occupied by the new handwriting recognizer database might be part of the problem - deleting the old handwriting recognizer files (PlecoDict HWR SC/TC ...) will free up several hundred K. And every custom dictionary you add increases the memory requirement (even on the SD card, it's more data that PlecoDict needs to cache and keep track of), so you could try deleting a few of those and see if that makes any difference.
koreth - we did fix the categories elsewhere, but we didn't fix them in the main screen because those lists are also used for a lot of other things - resizing the list based on the selected button is doable, but trickier than resizing it within the flashcard system.