Hello Tim
I am excited every time I hear someone is moving into 3D.
I'm not the most expert but I do have some expriance.
first of all
download AppGameKit 2.015b , so 3d physics will work and all new 3d commands.
second ,
when exporting from blender
.blend is a blender only file
you need to export to .dae
this is the new mainstream blender export for games and movies.. I know some uses the old formats which they are use to but the .dae is pretty simple , good and you can edit it outside blender inside the .dae file itself (xml).
third do not be afraid to play with all the 3d commands AppGameKit posses you might find it easier to understand then you think.
and the Cherry, write done Mixamo Fuse on google.. and get it while it is still free. you will be able to create wonderful 3d characters that you create and modify (you can modify everything) then export it to dae and play with it inside AGK.
do not forget inside FUSE preferences to click on "Pack Textures" as this will pack you character textures into 4 images that you then load with SetObjectImage(obj,IMG,shader) so you get a normal , specular and gloss I think..
hope this helps.