And where exactly did you read you need to downgrade 2.3.x to 2.1 in order to flash a custom ROM?
Calm down, turn the phone off and leave it on a charger for few hours in order to recharge the battery. Disconnect the charger, remove the battery, remove SIM and SD. Reinstall battery only, hold both volume keys and plug the phone to the PC. See Download mode now?
- BlackBerry Q10 LTE, 16GB int, BlackBerry OS 10.2.0 (main phone)
- Acer Iconia Tab A200, 16GB int, 16GB ext, ICS Android 4.0.3 (games tablet)
- Samsung i896 Captivate, 16GB int, 16GB ext, CM 11 Android 4.4.1 (backup phone)