Carbon Delta "should" be keeping your storage. Also in recent builds of Carbon they added the option to keep data/Xposed/density when flashing a new nightly (Persistence in Carbon Fibers). If you can still move files to your internal storage then it's definitely not a corrupt partition.
I'm not sure why it wiped your internal storage, sorry. Did you delete any folders in your storage when connected to a PC?
and i jst saw this in contact list the contacts pics are alphabets(for those i dont have pics). i want the earlier thing i there a way to get that. if i get the contacts app from the previous nightly and move it into the system will that work .