Thank you V_Kids for the quick reply...
Obviously, I'm adopting too the manual mode in taking photos. 
I'm provided with a Nikon D100 that adopts the D-TTL standard; this one has been abandoned by Nikon,
so it's quite impossible to me hoping to have some a different operative way in the future. 
The only chance I have is an external equipment like the one we are speaking to, even if I don't think this eq. will never include the D-TTL std in their TTL facilities. 
As chemical photographer I've used the TTL facilities for underwater macro shoots, and I've found this opportunity very useful.... If all this were available for digital photography also, I'd use it.
Anyway, I agree with you that this problem could be exceed, and this don't stop me (us) in taking photos underwater.... 
The other aspect is: It seems to me you all are fully satisfied of technical results of this flash, raising from a middle power flashes like the Y/S120 or similar....
I don't know any other people having bougth this flash at today, and till this morning I feel myself fully unsupported in the evaluation...
Thanks to you all, I think really I'll buy asap a couple of new flashes... You can try to ask Sea&Sea for your royalties.... I subscribe it...
Ciao... Thank you and "have good bubbles"