AEBSn - Unable to switch to 802.11n - Installation Bugged!

Question

If you have a fairly recent Mac and an AEBS which supports 802.11n (the Gigabit or "802.11n" model) then you are supposed to be able to get 802.11n which has advantages over 802.11g.
I run late-2006 iMacs and these are 802.11n possible machines, providing 802.11n has been enabled. Downloading the "2007-002" enabler is not necessary, as the enabler will tell you. That's because a similar enabler is embedded into the AEBS installer on the supplied disc.
I assumed that the instal process for the Gigabit AEBS would handle things automatically in terms of getting everything moving at 802.11n speed or at least allow easy selection.
Nothing like it. This is a warning to others.
I noticed in my Airport Utility that I was running at 2.4GHz and not 5GHz which is for 802.11n. So clever me decided to simply switch and restart my AEBS. (An incentive too was to move above all the shops across the road. They seem to have channels 1, 6, and 11 working hard.)
Lost my connection to the AEBS as a result of that. The AEBS instal process did NOT update my computers to support 802.11n. Can be checked via Network Utilities. I hadn't thought to check first.
133MAC in Australia were very helpful - they spent almost an hour working through things his morning. Top Notch support!
Solution required the Airport instal to be rerun but a lot of other poking around first in order that the embedded 802.11n enabler would indeed run. And you'll need a LAN cable and possibly need to move one computer over to the AEBS!
Couldn't find an Apple Knowledgebase article on this problem with the Airport instal disc but I suspect it is a known issue.
(I had nothing quirky in my network setup / machines. All using the most recent system software updates, default settings in network and sharing preferences and so on)

Answer 1

Yes I know about all that as these are the very options presented in the pop-up menu on the relevant configuration tab.
What I'm saying is that selecting the 5GHz option resulted in my iMacs being unable to communicate with the AEBSn through WiFi - the 5GHz spectrum.
Leaving the AEBSn in "default radio mode" as you call it will mean that it will actually be using 802.11g at 2.4GHz due to its inability to use 802.11n at 2.4GHz or 5GHz. The Apple Tech people I spoke to recognised this.
Many purchasers of the AEBSn, like myself, will really want to take advantage of the 802.11n capabilities in the 5GHz spectrum. They wish to dedictae the AEBSn to 5GHz throughput and deliberately exclude 802.11b/g on their AEBSn. Let some other boxes take care of that in the 2.4GHz range.
For a little home office thing with a mix of old and new clients the default setting for the AEBSn is a very good thing as the admin doesn't really care about throughput.