> The problem that I am having is that when I do so, I am having problems
> with some of my controls. If I have all my controls in the User services,
> they are not visible when I run the app, and they have a funny looking icon
> in their places in design mode.

Well, classes will only be visible in Visual Modeler if you have a diagram form them. Otherwise, they will only show up in the modeler's class browser. By default, no diagram is created, but you can activate that feature in the last step of the reverse engineering wizard.

> I have gotten it to where they all appear now, but I do not understand the
> criteria for which of the three tiers each type of class should be in. ie.
> should all buttons be in user services and all text boxes be in data services?

This really is up to you. I'd recommend to put everything but the custom classes in the user services. Custom classes usually are business services. However, there are lot's of exceptions. If you have a relation-class for instance (which is often the case for performance reasons) that is used to perform some business service, this class should also be in the business service tier.

However, also keep in mind that you can create your own categories. The plain three-category model is only useful for small applications (well, VM really seems to fit VB much better than VFP. Rational Rose would be the much better choice to be honest...).

> Also, do all buttons have to have an 'oHook' property to work? Are
> there other controls that need the 'oHook' property?

No oHook properties are required or even supported.

Markus