It comes down to this: ADE9X is designed to use the sdk tool MS has developed and provided to designers as their approved method for creating scenery for FS9/FSX. AFCAD and AFX do not use MS's tool. AFAIK, in the case of AFCAD2 that was for expediency, as AFCAD1 existed and Lee updated it before MS made the sdk available. Also AFAIK, AFX was designed as an extension of the AFCAD2 code. In extending the functionality of ADE to FS9, it was understood that a large base of AFCAD/AFX files exist in the community, and there would be interest in being able to update them. This requires the program reading the bgl code and attempting to convert it into the proper elements understood by the MS bgl compiler tool. It should be expected that there may be certain parts of an AFCAD/AFX created bgl that aren't directly usable without some sort of translation into MS bgl compiler, which might impact something. Also, it has been shown that multiple editing of AFCAD files can cause errors to creep into the resulting bgl due to things like rounding.Undoubtedly there are aspects of each tool's user interface that people will prefer to other approaches, in particular power users.scott s..

Edit of AFX file with ADE9X:I just had time to add a GA RAMP SMALL with accompanying tavi route to the main route across from Parking 48, compiled the file, placed it in a priority folder I use for AFCADs (this has to do with Radar Contact), and renamed the AFX file extension in the PAFA scenery folder. I then added the FRF PAFA airport to my scenery folder putting its priority with my other airport add-ons and restarted FS to reindex the scenery.I created a flight placing a GA across the aisle from the new parking point. The front cockpit view was normal as was the overhead showing the properly placed taxi lines and parking lines as expected. No crashes. The scenery looked OK and taxi signs were still present.I closed FS and then ran a scenery rebuild utility from within Radar Contact. I checked the utility log and the new parking area was properly recognized. Excludes from the AFX, ILSs, COM frequencies, taxi nodes, hold shorts, etc, were all carried forward as expected.It should be noted that only minimal parking for GA was placed into the East ramp because of several rows of static aircraft. If you wish not to see the static aircraft you can rename that file extension.At this time it does appear that it is safe to edit AFX files with ADE9X from my brief testing and adding parking with it meets the goals of the OP. I'll do more testing later.Another note regarding GA AI parking is I noticed the parking areas near 48 were all oriented nose out, not unusual for GA, and this is the designer's choice.Regarding AFX itself I noted in the scenery rebuild log I referenced the same global exclude instructions for runways and taxiways as appear in AFCAD. Now this log may not indicate totally what AFCAD may delete in that it is dedicated to runways, taxiways, navaids, and parking with other type of objects being skipped from logging. This goes along with some other replies about AFX being derived from AFCAD but offering a superset of facilties. Here's a partial text of how the Radar Contact scenery database rebuild utility saw the AFX derived replacement file created by ADE9X:Airport PAFA N64:48:49.2394 W147:51:34.8102 434ft City Name="Fairbanks" Airport Name="Fairbanks Intl" in file: ..\..\..\AFCAD2S\scenery\PAFA_ADE9_REG.BGL Delete all taxiways! Delete all runways and starts! *** DelBth *** PAFA0011 Lat 64.802628 Long -147.885956 Alt 434 Hdg 12 Len 11768 Wid 150 ILS 109.10, Flags: GS DME BC *** DelBth *** PAFA0012 Lat 64.815193 Long -147.847763 Alt 434 Hdg 12 Len 2631 Wid 60 *** DelBth *** PAFA0191 Lat 64.820869 Long -147.837296 Alt 434 Hdg 192 Len 2631 Wid 60 *** DelBth *** PAFA0192 Lat 64.828033 Long -147.839172 Alt 434 Hdg 192 Len 11768 Wid 150 ILS 110.30, Flags: GS BC Delete all taxiways! COM: Delete all frequencies! Runway 1L/19R centre: N64:48:55.1999 W147:51:45.2097 434ft Start 1L: N64:48:10.7873 W147:53:06.9057 434ft Hdg: 38.1 true Computed start 1L: Lat 64.802628 Long -147.885951 Offset Threshold primary: 750 feet Start 19R: N64:49:39.5802 W147:50:23.5125 434ft Hdg: 218.1 true Computed start 19R: Lat 64.828033 Long -147.839177 Offset Threshold secondary: 750 feet Hdg: 38.070 true (MagVar 26.000), ASPHALT, 11768 x 150 ft Primary ILS ID = ICNA Primary ILS: ICNA 109.10 Hdg: 38.1 , Flags: GS DME BC "ILS/DME 01L" Secondary ILS ID = IFAI Secondary ILS: IFAI 110.30 Hdg: 218.1 , Flags: GS BC "ILS 19R" *** Runway *** PAFA0011 Lat 64.802628 Long -147.885956 Alt 434 Hdg 12 Len 11768 Wid 150 ILS 109.10, Flags: GS DME BC *** Runway *** PAFA0192 Lat 64.828033 Long -147.839172 Alt 434 Hdg 192 Len 11768 Wid 150 ILS 110.30, Flags: GS BC Runway 1 /19 centre: N64:49:06.1492 W147:50:33.5643 434ft Start 1 : N64:48:53.2239 W147:50:57.2727 434ft Hdg: 38.1 true Computed start 1 : Lat 64.814598 Long -147.849608 Start 19 : N64:49:14.9281 W147:50:17.2135 434ft Hdg: 218.1 true Computed start 19 : Lat 64.822151 Long -147.835695 Hdg: 38.070 true (MagVar 26.000), GRAVEL, 3500 x 75 ft *** Runway *** PAFA0010 Lat 64.814598 Long -147.849609 Alt 434 Hdg 12 Len 3500 Wid 75 *** Runway *** PAFA0190 Lat 64.822151 Long -147.835693 Alt 434 Hdg 192 Len 3500 Wid 75 Runway 1W/19W centre: N64:49:17.2929 W147:50:40.9430 434ft Hdg: 38.070 true (MagVar 26.000), WATER, 5400 x 200 ft Runway 1R/19L centre: N64:48:27.3408 W147:51:45.0039 434ft Start 1R: N64:48:02.8183 W147:52:29.9152 434ft Hdg: 38.7 true Computed start 1R: Lat 64.800575 Long -147.875417 Start 19L: N64:48:46.7450 W147:51:09.2944 434ft Hdg: 216.3 true Computed start 19L: Lat 64.814613 Long -147.849589 Offset Threshold secondary: 200 feet Hdg: 38.070 true (MagVar 26.000), ASPHALT, 6500 x 100 ft *** Runway *** PAFA0012 Lat 64.800575 Long -147.875412 Alt 434 Hdg 12 Len 6500 Wid 100 *** Runway *** PAFA0191 Lat 64.814613 Long -147.849594 Alt 434 Hdg 192 Len 6500 Wid 100 COM: Type=8 (APPROACH), Freq=118.60, Name="FAIRBANKS" COM: Type=8 (APPROACH), Freq=125.35, Name="FAIRBANKS" COM: Type=8 (APPROACH), Freq=126.50, Name="FAIRBANKS" COM: Type=1 (ATIS), Freq=124.40, Name="PAFA" COM: Type=7 (CLEARANCE), Freq=127.60, Name="FAIRBANKS" COM: Type=8 (APPROACH), Freq=125.30, Name="EIELSON RANGE" COM: Type=9 (DEPARTURE), Freq=125.35, Name="FAIRBANKS" COM: Type=9 (DEPARTURE), Freq=126.50, Name="FAIRBANKS" COM: Type=11 (FSS), Freq=122.20, Name="FAIRBANKS" COM: Type=11 (FSS), Freq=122.45, Name="FAIRBANKS" COM: Type=11 (FSS), Freq=122.60, Name="FAIRBANKS" COM: Type=5 (GROUND), Freq=121.90, Name="FAIRBANKS" COM: Type=8 (APPROACH), Freq=118.10, Name="FAIRBANKS APPROACH" COM: Type=6 (TOWER), Freq=118.30, Name="FAIRBANKS" COM: Type=3 (UNICOM), Freq=122.95, Name="FAIRBANKS INTL"Lot's of parking and taxi data follow.Again, added or excluded objects like taxi signs and buildings, vehicles, etc., that may be in that AFX file are disregarded by this utility.One fun test might be to land a ski equipped GA on the water runway in winter to see if FS accommodates a frozen surface. That is runway 1W/19W in the airport diagram. In the scenery log above the water runway is not placed in Radar Contact data --- yet.