With help from the old timers here I've succeeded with importing my test object from 3dsmax 2018 into mcx, and finally, exporting the object into both an mdl file and bgl file. However, I have NOT yet succeeded in SEEING my object appear in P3Dv4. Along that line, I've uncovered some difficult issues with the scenery library in P3Dv4. I naturally assumed it would work as fsx did. However, now it appears there are two ways to import scenery (I don't yet know what seperates those ways). Using MCX to compile a bgl and setting up the normal files scenery and texture went as expected. Oddly, I couldn't find my object. Checked all the standard stuff, compiled for sparse setting, sim set for dense....triple checked the lat longs....remade my object so I knew it was big enough to see....double checked altitude was agl....disabled the orbix stuff in case their mesh was higher in altitude than default....nothing worked. No black object either, so it wasn't a texture thing.
So, I decided to delete that scenery library folder, and COULDN'T. It was frozen in the library. Turns out there is a method of install that puts the scenery location in a hidden folder on your C drive, and the placement file in MCX activates that method. I could disable that layer, using "options/addon", but the unchecked layer had to remain. Oddly enough, I couldn't see that layer in the scenery.cfg file. I found the folder with that scenery in C:\program data\Lockheed Martin\Prepar3Dv4 as an "addon". I deleted the file from there and received an error on first load of P3D. Then I deleted Scenery.cfg, and let P3D build a new one, which ended the errors, but also forced me to re-install the orbix stuff I have.
I did a bit of reading, and it appears this change in the Scenery config, Addon.cfg and new scenery compiling is new and confusing others as well. Its always something.
Finally, I compiled my test cube the old fashioned way by making a cube.xml file, and exporting with bglcomp. Then added the location manually into the scenery library which now behaved as expected. HOWEVER the object still does not appear in the sim. After that, I compiled the example of the oil rig, as shown in the sdk readme, and it also did not appear.
I'm sure this will be as well understood as it used to be, but more investigation is needed.
So, I decided to delete that scenery library folder, and COULDN'T. It was frozen in the library. Turns out there is a method of install that puts the scenery location in a hidden folder on your C drive, and the placement file in MCX activates that method. I could disable that layer, using "options/addon", but the unchecked layer had to remain. Oddly enough, I couldn't see that layer in the scenery.cfg file. I found the folder with that scenery in C:\program data\Lockheed Martin\Prepar3Dv4 as an "addon". I deleted the file from there and received an error on first load of P3D. Then I deleted Scenery.cfg, and let P3D build a new one, which ended the errors, but also forced me to re-install the orbix stuff I have.
I did a bit of reading, and it appears this change in the Scenery config, Addon.cfg and new scenery compiling is new and confusing others as well. Its always something.
Finally, I compiled my test cube the old fashioned way by making a cube.xml file, and exporting with bglcomp. Then added the location manually into the scenery library which now behaved as expected. HOWEVER the object still does not appear in the sim. After that, I compiled the example of the oil rig, as shown in the sdk readme, and it also did not appear.
I'm sure this will be as well understood as it used to be, but more investigation is needed.