Please see the most recent updates in the "Where did the .com name go?" thread. Posts number 16 and 17.
Please see this thread for updates. Update Thread
SOH ADMINISTRATIONYou need to open the sca file and manually modify the code to tell the game to load your texture as a poly and then compile it to a bgl with SCASM. Did you do that? FSSC does not compile the bgl so a poly texture will show. You get a solid color square.
Download Cody Coyote's Blended Airfield Tutorial and follow his instructions if you aren't already.
Good luck.