I just installed the GREAT Dreamfleet Beech A36. It's beautiful, not to mention the GREAT avionics included!
As I'm coming in on approach to Punta Gorda Florida, all textures except for the ones on the exterior of the aircraft, decrease in quality. I let the pictures talk.
(what it should look like on top, what they actually look like below)


Ground is also affected.


Naturally, those are highly compressed as this ain't a contest, but they get the point across.
Here's the kicker...to get the shots of how it should look, I had too minimize and then restore FS9. Then, for about 1.5 seconds after I un-pause it, the textures hold fine. Then, everything turns gray (like untextured models). Then, the textures reload, but in the extremely low quality as seen above.
>:( >:(

BTW, I just installed the A36 yesterday. It didn't cause problems when I started my flight in Delaware Mun, near my hometown. Thanks!