In the past, Yireo has seen so many Magento sites that were build using wrong procedures, resulting in corrupt Magento applications that could not be upgraded. The key here is that the customer (you) doesn't ask for quality with the right terminology, and the developer doesn't read the manual. Here are own guidelines, that hopefully can serve you to control your Magento modifications.
When optimizing your Magento shop for conversion, it is always good to pay attention to the Magento checkout success-page (URL checkout/success). You can thank the customer for purchasing, redirect the customer to a specific procedure. However, this page is only shown when you finish a Magento order. And after a refresh, this session is cleared - so a refresh of the success-page redirects you to an empty cart. This tutorial shows you how to improve this situation.
Using the new X.commerce, you can combine the power of Magento, PayPal and eBay (and many more services like Facebook) to create cool new applications in the cloud - or actually the XFabric. The X.com site explains you how to install the X.commerce Developer Package in Windows or MacOS. This tutorial explains the steps for Fedora Linux.
A Magento order could be cancelled by mistake, but there is no way to undo this action - at least not in the GUI. There might be excellent third party modules providing this functionality, but you could also write just a simple PHP-script to accomplish the same task.
This video-tutorial shows you how to inherit catalog images from a parent-category in subcategories of Magento. Instead of having to give each subcategory its own image, you can save yourself time by just reusing the parent-category's image if the current category has no image of its own.
The Magento e-commerce application makes use of events to allow third party extensions to hook into the Magento core-functionality. For instance, when a customer uses the one-page-checkout, multiple events are generated that allow other extensions to do their stuff. However, these events are not documented. While developing our own MageBridge extension, we needed to research on this ourselves - so here's the result.
Magento offers the possibility to let other applications connect to it through a Remote API. This API - based upon SOAP or XML-RPC - allows Magento to be integrated with other third applications like SugarCRM or OpenERP. This tutorial is the first in a series of four to explain you how you can use SOAP to connect to Magento.