Our controls are standard controls for WebForms built on top of the MS AJAX library (i.e., they offer rich client-side API and functionality that can let you reduce postbacks) and as such, rely on the general experience and knowledge developers have in the field. We do not offer training resources per se, but if you need to accomplish a certain task, you can browser through the control's demos and documentation in order to see whether the feature you seek is available built-in, and examine the API that can let you tweak it or create it:
The PDF Courseware is, indeed, outdated, and I would recommend going through the Overview and Getting Started articles in the documentation to get a general idea what each control offers so you can evaluate which one would fulfill the task you have at hand.
Considering the feature set and rich API our controls offer the learning curve for our controls can, indeed, be steep, but we offer demos and documentation that showcase their features so you can use that as reference during development. If you are stuck with something you can also ask us, even trial packages give you access to the forums and our support ticketing system.
Thus, while we do not offer training courses or creating custom solutions on demand, we may be able to point you in the right direction.
On accessing databases - this is not something our controls do themselves. They are user interface controls and providing the data operations is up to the developer (e.g., creating an SqlDataSOurce control with the appropriate Select, Update, Delete commands). In terms of data binding, our controls are not different than the standard controls (even though they offer many more events and API) and require standard data sources (e.g., IEnumerable or IQueriable collections, DataTables, Lists, etc.), so they can work with virtually any data source you can provide.
It is a general approach in WebForms to directly work with the data sources through controls like SqlDataSource or with custom code in the code-behind (e.g., calling stored procedures or extracting tables). It seems this is what you need, even though this is often cited as a drawback for the platform. Thus, security and performance are the developer's task and you must make sure to validate data and user inputs on the server.
I hope this covers your questions.
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