Interchange pros and cons...
My pleasure PeteC. I wish your user luck. Interchange has been given a lot of bad publicity, not only here, but in its own support groups.
After using it for almost two years, I can offer you and any other readers of this post my observations about Interchange.
It is one of the most potentially powerful and versatile applications available for Linux users, especially those wanting an E-commerce solution that can compare with the multitude of Dreamweaver friendly .asp and cold-fusion counterparts populating the web. For a few world-class examples of sites built with Interchange, see:
The main contender, mentioned in this forum and others, is the php application "osCommerce". In my opinion osCommerce has a lot of potential, but for sites requiring thousands of product items, the solution for importing "all at once" from a database is limited by another script called "Easy Populate". "Easy Populate" is not so easy, and has many limitations for those who need total control over all aspects of the "cart". For now, osCommerce is probably the better choice for those who need a cart that functions well with a couple of hundred items. If you write php and are proficient with CSS, you can do some nice things with the design capabilities of osCommerce. But when designing for companies with thousands of items, or distributors of several manufacturing companies, it's either Interchange or a windows solution. I tested at least 20 of the more popular Linux E-commerce solutions - ShopFactory, X-Cart, EdatCat, Actinic, cart-it, BizaarShop, etc. All expensive, and none as capable as Interchange, which is free to "learn with".
The learning curve with Interchange is not just "steep", if you don't at least know Perl (which I don't) and basic Linux it can be almost "vertical". To master Interchange, which I haven't, the user must have a good working knowledge of Perl, Linux, CSS, working with templates and the desire to learn the native Interchange Tag Language (ITL). I've built about six Interchange sites, and I've learned about 10% of what I wish I knew about Interchange.
The support for Interchange is ongoing and open to all. That support is especially useful if you know Perl and Linux, but even if you don't, they are willing to try to help the new Interchange user.
That support does not include Interchange when bundled with CPanel. The big problem with the Interchange / CPanel relationship is that CPanel is the "root" user of Interchange, and that causes problems with permissions when a customer of a hosting provider trying to use his CPanel installed Interchange learns early on he or she needs, among other things, the assistance of the hosting provider with such tasks as encryption, re-starting the Interchange Server at unpredictable times and any necessary tweaking of the catalog and interchange configuration files. Many hosting providers offering CPanel do not have the knowledge to troubleshoot Interchange.
Then the desperate user, not knowing any better, goes to the Interchange developers' group mailing list and expects support as though it was a "right". That's what set the Interchange developers' official policy of no support for CPanel / Interchange.
It's unfortunate that Interchange couldn't just be installed in an individual user directory, like adding PhotoShop to your C-Drive. That would solve many of the issues for CPanel Hosting Providers.
CPanel is brilliant. Interchange is brilliant. The Linux world needs as many positive unions of brilliance as it can forge to help it continue offering windows users more reasons to make the right choice when deciding on hosting providers.
Meantime, if you find you will ever need to offer your users the advantages of Interchange with CPanel, you can always consider leasing a dedicated server from cpanelhosting.com (no connection with cpanel.net, and I gain nothing personally from mentioning them). Those folks are not afraid to help with Interchange, and seem very capable of solving most of the more frequent issues, regardless of the time of day or night.
Best of luck,
[edited to remove all the uneccesary "cpanel ticket number lines"]