Ok so the issue happens when the fuel truck stops fueling the wings, when they reach full, and switches to fueling the center tank. Below is what my fuel load was for a flight i did last night, AMS-ATL. Another issue that happens that seems to be part of the original problem is the person over the fuel pit (from the ground hydrant) is either invisible or flickers. Just about a minute or so, maybe longer, it stops fueling after putting in either a few hundred or few thousand pounds of fuel in the center. I have not tested this with a tanker truck yet. I copied over the GSX config, listed below. Oh and the plane im using from SkySpirit Boeing 777-10X.
Arrival fuel in AMS was 52.7. When the fuel truck left, 138.5 was on it when i requested 192.2.
----B77X------------
FS Fuel Load (Boeing 777-10X series)
Load: 192.2 Lbs (Cap 350,410 lbs) (Wings: 138,020 lbs combo)
LM 69.01 (69.01 cap)
C 54.18 (212.39 cap)
RM 69.01 (69.01 cap)
--------------------
[aircraft]
nosegear = 31.47
refueling = 1
battery = 1
pushbackraise = 0
pushbackdummyevent = 0
pushbackcheckengines = 0
iscargo = 0
trafficcones = 1
preferredexit = 0
wingrootpos = 3.12 -1.95 3.05
wingtippos = 30.45 -13.46 3.05
fuelpos = -14.50 -0.25 0.75
waterpos = 1.00 -26.00 -2.00
lavatorypos = -1.00 -26.00 -2.00
gpupos = 1.25 30.50 -2.00
engine1pos = -10.68 6.25 -3.20
engine2pos = 10.68 6.25 -3.20
engine3pos = 0.00 0.00 0.00
engine4pos = 0.00 0.00 0.00
[exit1]
pos = -2.75 30.68 0.13 5.00
code = 1
name = Main exit L1
embeddedStair = 0
[exit2]
pos = -3.00 11.75 0.13 0.00
code = 3
name = Main Exit 2 L2
embeddedStair = 0
[exit3]
pos = -3.00 -16.00 0.18 0.00
code = 0
embeddedStair = 0
[exit4]
pos = -2.50 -27.82 0.18 -7.00
code = 0
embeddedStair = 0
[service1]
pos = 3.00 30.70 0.08 -5.00
code = 0
embeddedStair = 0
[service2]
pos = 2.75 -27.85 0.08 7.00
code = 0
embeddedStair = 0
[cargo1]
pos = 1.75 25.50 -1.92 -0.00
code = 2
name = Front cargo pit
embeddedStair = 0
uldcode = AKE
[cargo2]
pos = 1.75 -20.10 -1.92 0.00
code = 4
name = Rear cargo pit
embeddedStair = 0
uldcode = AKE
[cargomain]
pos = 2.00 -24.75 -1.67 0.00
code = 2
name = Bulk cargo
embeddedStair = 0
uldcode = BELT