Remember to make a copy of your personal data, eg. with the help of PimBackup WM2003 version, as all those information will be lost.
A backup of the OS you use now is usefull, too. In case something goes wrong or you are not confinced of the WM you flashed.
Most important is that you read carefully first, all information you can get about flashing and the rom you want, untill you are really sure about it. Good luck, and nice to see you here. There should be no prob to flash, in case you are well prepared.
In case someone of you finds any mistake in spelling, punctuation or grammar in my posts - you can keep it !!!
Any language is Freeware - you can use it for FREE!
But, remember: They are not Open Source, you can't mutate, modify or falsify the Code, as you like to.