Clow in Tsubasa

As TRC and HOLiC are connected (see the HOLiC section before reading this), we know that alter Sakura and Syaoran and their welfare are part of Clow's plan. Moreover, a mysterious man is after that alter!Sakura's memories; this man's name is, not coincidentally, Fei Wan Reed/Read. As we see for his last name, he must be Clow's relative, or maybe even descendant. This villain has big grudges against Clow and Yuuko, also.

But this is not the end of Clow's intervention in Tsubasa. In another world, there's a kingdom on the desert called "Clow". In this country, the king is an alter!Touya, while the alter!Sakura I mentioned before is his sister. But that's not it, since from the flashbacks from princess Sakura's childhood, we see her deceased father, the previous king, looked exactly like Clow Read. Was alter!Clow also a magician? How much of his daughter's fate did he know? What's the connection between him, Clow the magician, Yuuko, and/or Fei Wan? What's the secret behind Clow country's ruins? I wish I knew.