Batch Update Mp3 tags

I need a utility to read a CSV text file. The file can hold unlimited number of records and each record has a path to an mp3 file and a reference number. I need the utility to go to the mp3 file and insert the reference number in the APEv3 part of the MP3 tag. The reference number needs to be inserted in the "client" feild. If there is no Client feild in the tag then one needs to be created and then entered. The utiltiy must do this for each line of the csv file automatically. I need the utility to be able to read a directory and subdirectories and produce a txt report as to which mp3 files do not have Client data in the mp3 tag files. Attached is an example of the csv. txt file