1) which phone are you trying to port the ROM?
2) which phones ROM are you trying to port?
BTW you just can't port the whole folder of system or anything! Be very choosy and port only the .apk's which WILL work on your device i.e, the ROM you are trying to port to your phone should have the same specs as your phone!
For ex. I am trying to port a galaxy s3 ROM to a galaxy ace, which won't work as the s3's CPU is much more high and takes a lot more processes at one time, which an ace can't handle and will thus give me a lot of FC errors!
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