i would like to know if you download something from another source other than the built in market facility, how do you go about transferring onto the phone from the pc when connected via usb
When you first hooked your X10 up to your PC it should have instal SE PC Companion, if so far right option is file manager. You need to put the app on the sdcard and then use an app installer, I use the app manager in ASTRO File Manager, just find the folder with the app in, tap the apk and select "Open app manager" and then "install".