You really shouldn't be creating adapters manually unless under very extreme circumstances....the framework provides you with all of the connection and access you need. First of all, this is a basic feature that StrataFrame provides...list population. You should be using the PopulationDataSourceSettings property and have it populate on the FormLoad. You can find some more details in the help documentation or you can look at some of the samples that come with the framework. Before I go into any more explanation I want to make sure that I haven't missed something in your post.
You are just wanting to populate a list or combo with some data that can be shown to the end-user and possibly bound to a field as well...correct?