The changes to the original code is rather minimal. The Austpost distribution files detail exactly what needs (needed) to be changed, so even if I'm not around to perform patches for future updates it is a trivial thing for someone else to do.
Having said that, as per the AP documentation, you DO NOT NEED to update or replace the files in the /admin/ area for things to work.. Those files simply provide a means for you to enter the dimensional data for your products. Unless you are selling products subject to cubing rules, or letter sized items you won't even gain any real benefit by using dimensions.
At the time this module was developed there were no overrides for the /admin/ files. I believe this has been changed since V1.3.8, and where possible any new update will always use whatever overrides are possible.
The same as with any other 3rd part module. Either wait for the author of the module(s) to release a new update (or confirm compatibilty), or, in the case of the AP module, you generally won't have anything to worry about.
Only if you wish to obtain quotes for all product types.
Please read the 'servers.txt' file. There are two servers used for different purposes.
The VCSWEB site has been around in one form or another since 1997. (originally 'videocam.net.au')
In contrast, the 'Australia Post' server (actually just another 3rd party server located at drc.edeliver.com.au has only been around since 2003 (or thereabouts).
In the last twelve months the drc.edeliver server has been offline for periods of >2hrs no less than 8 times. (I log this stuff). It has been offline for more than 48 hours twice.
In contrast, the VCSWEB servers have had a *total* of 2hours downtime over the last 12 month period.
So basically, the VCSWEB servers have a far better 'breeding' and tend to be more reliable than the 'official' server.
And finally, (future plans revealed) the next version of the AP module will only be supported by the vcsweb servers. Not because of any selfish type reasons, but because, frankly, the drc.edeliver server kinda sucks for the purposes that we are using it for. It is/was only designed to produce a single quote, and only for parcel post. In order to get a list of all possible quotes, multiple server requests are required.
What a shopping cart want/needs (in my opinion) is a server that will produce a list of all suitable methods and costs for any given parcel with just a single request.
I've 95% completed the server side software (which produces output in .XML format for easy client side integration).
I had almost completed the client side coding for zencart when I had a RAID failure, and as yet I still haven't recovered the code. :-(
Anyway, the ultimate aim is to produce a postage calculation server that can be more easily utilised by *any* shopping cart software (not just zencart). A server will produce shipping *options*, rather than one that produces a single quotes.
Bottom line here is that even though we've already been around for over a decade we still have even longer term aims and goals.
Cheers
Rod