Seems to be a few bitter people out there, most of whom declare that they do not enter the event, so why try to drag it down ?
As I see it there are two issues
machine eligibility - The object is to try to keep the bikes looking as close to old bikes as possible. The horse has well and truly bolted, so it is generally accepted that parts made from exotic materials but look something like the originals are OK. Similarly billet yokes are accepted as it was technically possible for a bloke with a drill and a file to make a set back in the day. The organisers have two options, write a massive set of regs trying to cover all machines and all possible mods or keep it simple and say "pre 65 design". I would guess the reason for the A4 photo's is to give the organisers chance to challenge anything they are unhappy with before the ballot( assuming you have the good sense to send your entry in before the last minute).
Exclusion from the event- As far as i am aware the 5 riders were allowed to ride on a no award basis. This was because they had parts different to those declared on their entry. I understand this was a warning shot and riders doing the same again will not be allowed to ride.
As far as turning a blind eye to other bikes and allowing cheating, this is not the case, the bikes complied in terms of parts declared on the entry, but in the view of the machine examiner were pushing the envelope too far in terms of pre-65 design. These riders were told what they needed to do to bring their bikes back in line.
so in my opinion it is quite simple, use pattern parts in exotic materials so long as they resemble the original, don’t modify your frame beyond recognition, and ask the organisers if in doubt.