I don't know why, but I'm not seeing the bottom-of-descent arc on my MFD with my home pc.
I saw it reliably on my laptop and so far as I know I have the current version from ISG.
Here's a copy of my cfg file:
LoadFuelonFlightPlanLoad=1 // Load Fuel automatically when Flight Plan is loaded into FMC or MCU
SetDestLoadTowerViewDist=20 // The distance from the destination airport when the tower view is changed to the destination (FS9 only)
SetMCUToPageOnFPlanLoad=1 // Set the active page on the MCU to the 'TO:' page when a flight plan is loaded.
DispAppPtrnAlts=1 // Display Approach and traffic pattern alts
ShowTodBodIndicators=1 // Show TOD/BOD indicators
DispPrevWpt=1 // Display Previous flight plan waypoint (MFD,EHSI).
ParkingFile=isg_parking.txt // Parking positions file
WptProcChgDist= // Waypoint change distance for procedures (Sid,Star, etc)
WptChgDist= //The distance (Lnav) the autopilot switches to tracking the next waypoint
VnavSetAlts=1 //Does not set altitudes when VNAV is on (default is 1)
VrefMin=115
BestHoldIas=140
MFDTextAntiAlias=1
ModelId=Beechcraft Premier
VnavSetSpd=0
WptChgSecs=10
WptProcChgSecs=10
DrawBodArcOnP1000MFD=1
Seems like the last entry should enable this function...