Hi everyone, sorry for any frustration regarding the deprecation of Personal Projects.
Unfortunately, the import/export process with CSV does no include attachments and comments, however, this might be possible with third-party apps like Ditto.
Please note that we cannot provide support for the Ditto integration, as we did not develop it, but we frequently see it used by our customers and recommended by our Community members in posts like this. You can find the Ditto integration here: https://ditto.kothar.net/
I hope this helps!