I know it's not what you asked you but have you looked at youtube?
There are a few videos there that looked helpful for the basics. Even one specifically about FSX and gmax from the fsdeveloper conference.
BTW that textures appearing and disappearing sounds like 'view material in the viewport'. Click that blue button on to render the texture 'bitmap' in the viewport.
Also check out toprob's tutorials that I started with, when did you put these together? What 10 years ago, Rob? Very helpful.http://windowlight.co.nz/store/index.ph ... &chapter=1