After Sp2 install (see attached system details) I selected my ONLY add-on https://flyawaysimulation.com/downloads/files/1427/fsx-cessna-l-19d-o-1d-model-305c-bird-dog-military/
FSX - Cessna L-19D (O-1D) model 305C, Bird Dog, Military version on wheels L19D_FSX.zip
And part of the cowl is missing, also there's a hole below the elect panel, the panel used to be gray and the stick is new! But ONLY in this FSX view mode. Other view modes (fixed spot, 3-D cockpit) are normal. The FSX default piper cub came through Sp2 install OK.
I use X_Graphics to customize various FSX surfaces, and those were replaced with SP2 defaults. Was able to re-install the X_Graphics themes I like, no problem.
I also run FSX_GA_Traffic for extra AIs and they work as before.
I suppose, even running FSX on Xp with DX9, we gotta be careful of what old add-ons we install..
With this computer:
Intel DP965LT ATX mainboard (P965express chipset)
Intel onboard Azalia sound & 82566c LAN
intel Core2Duo E6600@2.4ghz
Generic intel approved thermally advantaged ATX case
Thermaltake 775D copperbase heatpipe cpu cooling fan
Corsair 4x1gb duel channel DDR2@667mhz
Gigabyte nVida 8800GTX w/768mb DDR3
Memorex DVD-CD R+RW drive
Western Digital 1600YS SATA hardrive
Antec NeoHe 500watt power supply
Samsung 215TW 21" widescreen (1680x1050) DVI LCD
Samsung CX213TW 13" DVI LCD
CH Flightstick Pro usb & Ch control manager V4.2
Ya there are others having issues with addon aircraft and sp2. I guess you would have to get with the plane's author for a fix. You could try deselecting dx10 in the graphics options which may or may not help.
Because I'm running FSX Sp2 on winXp OS I don't have the DX10 preview option, so this is DX9c.
Since inital post I've updated the vid card driver to current nVida and deleted & installed a new download of the L-19 to no effect, it's a hard fault.
I won't install another addon (payware or free) until the details specifiy; "works with FSX Sp2".