Only to give you a hint.
Before starting AppGameKit programming, I have been programmed about 1 year and half with DarkBasicPro, creating one 3D games and 4 2D games.
After the first game, I have realized that DBPro Sprite commands are quite annoying, so I created (in advance of AGK) a library of functiona of the kind: getSprite<XXX> and setSprite<YYY> in order to speed up creation and management of Sprites. I added a lot of other features too (creation of scrolling background, field stars, etc), but what is interesting is the similarity of my commands syntax to AppGameKit one. Moreover this commands rely on a custom type data structure that contains all informations about the sprite.
Only to give an idea, the list of function signatures can be found at
http://darkbasicgames.altervista.org/GameLibraryHelp.htm.
This is my idea: to adapt this library to AppGameKit syntax, in order to make porting straightforward.
If you are interested, I can give you the code, for free of course, and you can adapt it. I think that for Windows, DarkBasicPro is much better, it generates self-contained executables and it is free.
I advice to start with DarkBasicPro, have some experience waiting AppGameKit product being a little bit more mature, stable and include 3D commands, and then buy AGK.