Hello again Ian,
First, the problems you are describing apply to the specific case of a flatbed scanner in which you batch scan a number of photos at a time. People using film scanners would not experience most of these issues. In any event, I think it's always a good idea to try demo versions before buying.
Second, it is correct that a small handful of lesser-used features from SilverFast Ai6 have not been ported to SilverFast 8. The reason for this is that the whole program was redrafted from the bottom-up in a new and improved code base. In doing so, my understanding is that they needed to make decisions along the way about which features to keep, improve or drop. The items you mention were dropped (but you can do renumbering) - I would assume because in their judgment (based on what they know about how people are using the applications) they weren't important to enough users to justify the cost of redeveloping them. If enough people want/need them, I can imagine that they may have a second thought. There's really nothing "amazing" about any of this - time is money and business firms need to think of how best to use it. Only us users can alter their perception of that by bringing matters such as this to their attention, so they have enhanced information about priorities from user-perspectives. You can ask them directly, but I expect an HDR8 version should be not far off.
As for freezing up, I haven't had that experience (MacPro mid-2010, OSX 10.6.7). As for memory leaks, so far I haven't seen the kind of degraded performance suggesting same, but perhaps you could elaborate how you found memory leaks, and at the same time mention the computing environment in which you are using the application?
