Troubleshooting: here
iMJalv2 - Guide (below)

Uploading Ringtones /Wallpapers
Connect to phone.
Click Download – locate the file – click open.
When prompted with “Load file example.wav as ringtone ” click yes. ( same applies for wallpapers)

Uploading Java Applications (Games)
Connect to phone.
Click download and locate both the .jar and . jad files.
Upload both files.

Removing and Replacing Camera Sounds (all camera phones)
If you wish to use a replacement sound, make sure its 8000hz, 8bit, mono, and only 10 seconds or less. If you wish to have silence, simply stop after step 4 and set the camera sound to the one you deleted.

1-Connect to phone
2-go into " shutter_sound " folder
3-select either 1.wav or 2.wav
4-click the Remove button and it will delete this camera sound. This cannot be undone (you can stop at this step to have completely silent camera sound when the camera is set to that sound)
5-once removed, click Download and select your replacement.
6-When prompted, select No so you DON'T load it as a ringtone .
7-After your replacement 1.wav or 2.wav is entered, click on it, then click Type
8-Set the type to 17 and click OK
9-Disconnect and check it out.
Replacement sounds too large or too long will power the phone off!

Replacing startup images
Here's info on how to replace startup images.
First, be 100% positive on your phone's true screen sizing. ex : i860 is 176x220, i730 is 130x130.

also know the following info:
carrier_img.gif is the Nextel image when powering up
text_img.gif is the T9 Text Entry image when powering up
java_img.gif is the Java powered image when powering up
pwrdown_img.gif is the Powering down image.

Make your replacement image in the following format :
Image has to be correct sizing (i870 = 176x220)
Image has to be animated (no more then 2 seconds per image, and don't make it loop, only make it play once and stop playing)

If you have images that can replace that, then do the following:
1-Take your replacement image, and rename it to the startup image you want to replace. If the startup image you want to replace is carrier_img , then rename your image to carrier_img and continue to step 2
2-Click the image you want to replace, and click Remove
3-Click Download, and select your new image
4-If prompted, do not load as wallpaper and it should load perfect and power up perfectly.
Replacement images not correct can freeze the phone when powering on!