Tips from someone who's bricked countless phones, and used to be one of the drones that used fancy cables to reprogram them:
Be sure you have a reliable way to return to where you started.
Try installing the apk as a normal file
Try installing the apk as root via adb
Try pushing the apk to the correct location
Try pushing the apk to the correct place while in recovery
Try installing the apk through recovery (as an update)
Never waste time trying any of this without logging via logcat if possible
always start logcat at reboot asap if possible
have plenty of cheap beer on hand.
Files that have other dependencies, or that have been modified by the carrier (like brandon's browser

) will need dis-assembled, edited, and repacked/resigned. Google apktool and deodex to learn more about that. Hit eBay for a CDMA Android phone that has a bad ESN to practice on -- they're cheap. Don't practice on the device you use every day, or one day you'll have to go without it
