you have to push the fm apk into /system/apps. Check his forums for how to do it.
I think its HtcFmradio.apk, just use its name.
This is how I reinstalled the oneyouwant.apk file. Forgive me if I am being too simplistic.
1. Connect USB cable from computer to phone and boot the phone into recovery mode
2. On the computer, go to "Start", then "Run" and enter "cmd" and then enter to open the command prompt (or any of the other methods to open a command prompt)
3. Within the command prompt, navigate to where your sdk/tools folder is at (use "cd.." and enter to go up in the directory and "cd folder name" to enter a folder within the open directory
4. Enter "adb shell mount /sdcard"
5. Enter "adb shell mount /system"
6. Enter "adb shell"
7. Enter "cp /sdcard/fresh-removed-apks/oneyouwant.apk /system/app"
8. Reboot the phone
FYI - If using Windows7, you can copy the commands from here and paste into the command prompt.