I bet you're right.

If the C4 dealer has a Houselogix account, they have an updated Somfy driver that utilizes some of the new capabilities of the blinds proxy in C4's latest OS, version 2.9. I just used this driver with the URTSI II interface in my first shade integration with C4, and everything works great. As tweeterguy mentiined, you can also use the URTSI II driver that's already in the database without throwing any more money at it.