Here we go...
1. In theory, yes. Sprint and most all other vendors will not accept a phone that has a custom rom on it for return. Likewise they often refuse to work on a phone from a support stand point if there is a custom rom on it. So if you flash a custom rom and have hardware issues, flash back to the latest stock rom and then return the phone.
2.
spb Backup does a backup of all the software and settings so that it will automatically put everything back the same way you had it each time you flash a new rom on your phone. Very cool feature. Other backup programs like
Sprite Backup also work well. None of the good ones are free.
3. Most do, they should say in the rom release. I have not seen any Diamond roms that are not based on WM 6.1.
4. You can donate to the person who releases the rom that you like most, or you could donate to PPCGeeks, or both or neither. The great thing about this community is that donations are not required, they are just another way of expressing your thanks for this site and all the work the community does here.
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