Post-root troubles

Thanks to this reddit I was able to successfully root my Desire and I love all the internal memory that it has cleared up. But now I have troubles.

First is that apps that are installed on the SD card that use a widget. If I unmount the SD for any reason (including hooking up the USB to my PC), when I re-mount the SD card those widgets are no longer usable. They don't even show up on the widget list.

Second, if I transfer or download files to the SD, I can't access them with any apps. For example, if I download an mp3 from Dropbox, it won't show up in Winamp or any other app until I reboot my phone.

I'm thinking that these problems are probably connected somehow, but could someone tell me what I did wrong?

For the record, I am running rooted on a stock 2.2.