Thank you !By data if you mean apps and appdata then you can just flash any working build directly . just wipe cache and dalvik cache. It won't delete your data.
There is apparently also another solution to make the current nightlys work (replace /system/lib/libcutils.so).
More information in the official cyanogenmod forum. I can not post the link unfortunately.
The thread title are "CM13 stuck in boot loop".