Yeah, the W700 is CID49 so you will have to use PhoneXS everytime you want to customize something in the FS which means you have to flash the main after that. But as you mentioned you need to finalize it you can try this:

- download the needed custom files
- open your phone with phonexs and grant it's access to far manager by flashing 5 blocks of MAIN
- put the custom pack files with far into: tpa\preset\custom
- flash the MAIN again

It should work now.