We usually are told around $20K, but Arecont has said "Register one camera if you have to".
Really not a fan of the "project registration" thing. Wastes more of my time filling out paperwork and most of the time the manufacturers want your end user info BEFORE the project is sold. Just give me my pricing so I can get it loaded in my quoting tool. Then I can rip out quotes without have to haggle with you for the best price every time I send out a quote out.
Axis used to start at 10K but if the project wasn't over 25-30k you wouldn't see more than a courtesy point...
As a manufacturer's rep I usually use $40K (Canadian dollars) or that the project must be "strategically important". I don't register projects without a real project name, I don't need or want actual contact information. In most cases I provide project registration through a distributor but with the condition that the special pricing is tied to the one distributor. If the dealer shops the special pricing to multiple distributors I won't register the next project.
For me, the bigger issue is that most of my manufacturer's only allow 2-3% for registration which is not enough to offer real insulation on a project.