[469c] Crash on try export texture in editor

[SeriousBuggie]

Reproduce:

1. Open BadTexture.zip in UnrealEd
2. On MyLevel.Skins.Jpine1 right click and try export texture to png
   

Expected result: Texture exported, no crash.
Actual result: crash.

General protection fault!

History: UTextureExporterPNG::ExportBinary <- UExporter::ExportToArchive <- UExporter::ExportToFile <- UEditorEngine::Exec <- 
(OBJ EXPORT TYPE=TEXTURE NAME="MyLevel.Skins.JPine1" FILE="Z:\UT_469c\System\Scr)..
SE(C0000005) @ 5E2F15AB
fl=0 rec=0 n=1578908544 i[0]=0 i[1]=10
eax=5cef1d08 ebx=00000000 ecx=00000010 edx=1f0f53a6 esi=00000000 edi=192483f4 eip=5e2f15ab
ebp=01179d64 esp=01179c9c cs=0023 ds=002b es=002b fs=0053 gs=002b flags=00010246
In module 'Z:\UT_469c\System\Editor.dll' at address 000515ab
 <- WBrowserTexture::OnCommand <- WM_COMMAND

Such happen for all export formats.

[SeriousBuggie]

UCC fail too:

>..\System\ucc batchexport BadTexture Texture png z:\
=======================================
ucc.exe: UnrealOS execution environment
Copyright 1999 Epic Games Inc
=======================================

Loading package BadTexture...
General protection fault!

History: UTextureExporterPNG::ExportBinary <- UExporter::ExportToArchive <- UExporter::ExportToFile <- UBatchExportCommandlet::Main
SE(C0000005) @ 5E1615AB
fl=0 rec=0 n=1581136768 i[0]=0 i[1]=10
eax=5cef1d08 ebx=00000000 ecx=00000010 edx=000017c3 esi=00000000 edi=0358aa8c eip=5e1615ab
ebp=012ff488 esp=012ff3c0 cs=0023 ds=002b es=002b fs=0053 gs=002b flags=00010246
In module 'Z:\UT_469c\System\Editor.DLL' at address 000515ab

Exiting due to error

[SeriousBuggie]

There only CompMips. no usual one. So info in editor about P8 too wrong.