I've created a custom heightmap for my custom race's homeworld by cropping together several of the other continents, but now that I've started trying to use it, the game crashes on launch. I suspect it's because I'm doing something wrong. I know it's my mod, because as soon as I remove the mod, it works again. Rather than try flicking every switch in Photoshop's Save As dialog for .dds files, could someone who knows better please tell me what settings it needs to have? If you don't know what I mean, here's a picture:

Also, while looking through the base game's custom_heightmap folder, I found a .dxatlas file. Do I need to do anything with that in any way, and if so, how?
If anyone needs to see my debug.err, here:
Debug Message: Version 1.02, Build #205, last updated on: 09-03-2014 00:17
Debug Message: Activation successful.
Debug Message: Entering WinMain
Debug Message: ******* Starting Game Shell *******
Debug Message: Command Line:
Debug Message: InitializeCrashReporter.
Debug Message: InitializeResources.
Debug Message: Initializing Shell
Debug Message: Initializing Fonts
Debug Message: Initializing Fonts - complete
Debug Message: Initializing Direct3D
DebugMessage: Particle Engine Created.
Debug Message: Adding DXSAS clean up function
Debug Message: Initializing device
Debug Message: DrawManager InitializeDevice
Debug Message: Creating renderer
Debug Message: Initializing Direct3D 11 Renderer
Debug Message: Creating animation core
Debug Message: Creating animation core
Debug Message: Enumerating device settings
Debug Message: CD3D11RendererSettings::Enumerate: Preferred adapteris 0
Debug Message: CD3D11RendererSettings::Enumerate: Creating DXGI 1.1 factory
Debug Message: CD3D11RendererSettings::Enumerate: Enumerating adapters
Debug Message: CD3D11RendererSettings::Enumerate: adapter enumerated
Debug Message: CD3D11RendererSettings::Enumerate: Adapter 0
Debug Message: CD3D11RendererSettings::Enumerate: Description: AMD Radeon HD 6700 Series
Debug Message: CD3D11RendererSettings::Enumerate: Vender ID: 0x1002 (4098)
Debug Message: CD3D11RendererSettings::Enumerate: Device ID: 0x68bf (26815)
Debug Message: CD3D11RendererSettings::Enumerate: SettingsLevel: 3
Debug Message: CD3D11RendererSettings::Enumerate: Enumerating outputs for adapter 0
Debug Message: CD3D11RendererSettings::Enumerate: 45 display modes found for adapter 0, output 0
Debug Message: Preferred Adapter Description:
Debug Message: Description: AMD Radeon HD 6700 Series
Debug Message: Vender ID: 1002 (4098)
Debug Message: Device ID: 68bf (26815)
Debug Message: Choosing initial renderer settings
Debug Message: Setting resolution to 1152 x 648
Debug Message: Initializing Renderer APIs
Debug Message: (CD3D11Renderer) Initializing driver
Debug Message: CreateDeviceAndSwapChain
Debug Message: DirectX Feature Level: DirectX 11.0
Debug Message: Device SUPPORTS compute shaders
Debug Message: Initializing 2d screen space effect
Debug Message: Device is now ready
Debug Message: Registering text renderer icons
Debug Message: FXManager, FXElement size: 712 bytes
Debug Message: Shell initialization complete
Debug Message: Shell Initialized
Debug Message: CGalCiv3Shell::RequestInitializationState from: Invalid to: Uninitialized
Debug Message: Running DXAtlasDLL Generator Program
Debug Message: Finished running DXAtlasDLL Generator Program (C:\ProgramData\Stardock\Galactic Civilizations III\Screens\Atlas)
Debug Message: Loading texture atlas
Debug Message: Finished loading texture atlas
Debug Message: Initializing PerPixelHitdata and ScreenControlFactory
Debug Message: ***** Initializing Game *****
Debug Message: OpenDirectory FAILED for directory: D:\Games\Steam\steamapps\common\Galactic Civilizations III\Screens\Schema
Debug Message: Timer Frequency is 0 35a52d
Debug Message: CGalCiv3Shell::RequestInitializationState from: Uninitialized to: Initialized
Debug Message: Initializing sound card
Debug Message: Loading mods
Debug Message: Creating anchor win
Debug Message: Create popup manager
Debug Message: No files found matching mask Sfx\*.wav
Debug Message: No files found matching mask Music\*.ogg
Debug Message: No files found matching mask D:\Jon's Documents\My Games\GalCiv3\Mods\Sfx\*.wav
Debug Message: No files found matching mask D:\Jon's Documents\My Games\GalCiv3\Mods\Sfx\*.msscmp
Debug Message: No files found matching mask D:\Jon's Documents\My Games\GalCiv3\Mods\Music\*.mp3
Debug Message: No files found matching mask D:\Jon's Documents\My Games\GalCiv3\Mods\Music\*.ogg
Debug Message: Initializing bink
Debug Message: CInfluenceSystem::CInfluenceSystem size_influenceMapActual 2359296 size_influenceMapCache 2359296 size_lastTurnOwningPlayerIndex 589824 size_prevOwningPlayerIndex 589824 size_owningPlayerIndex 589824 size_isSectorChanged 9216 size_numOwnedTiles
Debug Message: Game XML has been changed: Yes
Debug Message: ERROR: GetTranslation() failed
Debug Message: ERROR: GetTranslation() failed
Debug Message: ERROR: GetTranslation() failed
Debug Message: ERROR: GetTranslation() failed
Debug Message: ERROR: GetTranslation() failed
Debug Message: ERROR: GetTranslation() failed
Debug Message: ERROR: GetTranslation() failed
Debug Message: ERROR: GetTranslation() failed
Debug Message: ERROR: GetTranslation() failed
Debug Message: No files found matching mask D:\Jon's Documents\My Games\GalCiv3\Factions\*.faction
Debug Message: CGalCiv3Shell::RequestInitializationState from: Initialized to: LoadingContinentTextures
Debug Message: Running DXAtlasDLL Generator Program
Debug Message: Finished running DXAtlasDLL Generator Program (D:\Games\Steam\steamapps\common\Galactic Civilizations III\Gfx\planets\generic_heightmaps)
Debug Message: Running DXAtlasDLL Generator Program
Debug Message: Finished running DXAtlasDLL Generator Program (D:\Games\Steam\steamapps\common\Galactic Civilizations III\Gfx\planets\custom_heightmaps)
Debug Message: Running DXAtlasDLL Generator Program
Debug Message: Finished running DXAtlasDLL Generator Program (D:\Games\Steam\steamapps\common\Galactic Civilizations III\Gfx\planets\custom_base_heightmaps)
Debug Message: Creating initial screens
Debug Message: Create setup screens.
Debug Message: Creating remaining screens
Debug Message: Set mouse
Debug Message: Set update timer
Debug Message: CInitializationGfxListener::OnLoadContinentsTextureTailA
Debug Message: CInitializationGfxListener::OnLoadContinentsTextureTailB - All continent per-pixel data is now available
DebugMessage: *********DXDiag info follows.*********
System Info
Time: 5/28/2015, 01:55:34
DirectX Version: DirectX 11
Machine Name: OPENHEART
Operating System: Windows 7 Home Premium 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_gdr.150427-0707)
Languages: English (Regional Setting: English)
System Manufacturer: BIOSTAR Group
System Model: TA990FXE
BIOS: BIOS Date: 02/29/12 17:51:48 Ver: 04.06.04
Processor: AMD FX(tm)-4100 Quad-Core Processor (4 CPUs), ~3.6GHz
Physical Memory: 8192MB RAM
Page File: 6115MB used, 10154MB available
Windows Dir: C:\Windows
Display Info
Display device 1:
Device Name: \\.\DISPLAY1
Card Name: AMD Radeon HD 6700 Series
Manufacturer: Advanced Micro Devices, Inc.
Chip Type: AMD Radeon Graphics Processor (0x68BF)
DAC Type: Internal DAC(400MHz)
Key Device: Enum\PCI\VEN_1002&DEV_68BF&SUBSYS_31401682&REV_00
Display Memory: 742 MB
Current Display Mode: 1776 x 1000 (32 bit) (29Hz)
Monitor Name: Generic PnP Monitor
Monitor Max Resolution:
Driver Name: aticfx64.dll,aticfx64.dll,aticfx64.dll,aticfx32,aticfx32,aticfx32,atiumd64.dll,atidxx64.dll,atidxx6
Driver Version: 8.17.0010.1333
Driver Date: 11/20/2014 19:44:20
DirectX Acceleration Enabled: Yes
Sound info
Sound device 1:
Description: Speakers (Realtek High Definition Audio)
Default Sound Playback: Yes
Default Voice Playback: Yes
Hardware ID: HDAUDIO\FUNC_01&VEN_10EC&DEV_0892&SUBSYS_15658224&REV_1003
Manufacturer ID: 1
Product ID: 100
Driver Name: RTKVHD64.sys
Provider: Realtek Semiconductor Corp.
Driver Version: 6.00.0001.6343
Driver Date: 4/6/2011 15:33:48
Type: WDM
Other Drivers:
Acceleration Level: 1
Cap Flags: 0
Min/Max Sample Rate: 0, 0
Sound device 1:
Description: Realtek Digital Output (Realtek High Definition Audio)
Default Sound Playback: No
Default Voice Playback: No
Hardware ID: HDAUDIO\FUNC_01&VEN_10EC&DEV_0892&SUBSYS_15658224&REV_1003
Manufacturer ID: 1
Product ID: 100
Driver Name: RTKVHD64.sys
Provider: Realtek Semiconductor Corp.
Driver Version: 6.00.0001.6343
Driver Date: 4/6/2011 15:33:48
Type: WDM
Other Drivers:
Acceleration Level: 1
Cap Flags: 0
Min/Max Sample Rate: 0, 0
Sound device 1:
Description: Realtek Digital Output(RCA) (Realtek High Definition Audio)
Default Sound Playback: No
Default Voice Playback: No
Hardware ID: HDAUDIO\FUNC_01&VEN_10EC&DEV_0892&SUBSYS_15658224&REV_1003
Manufacturer ID: 1
Product ID: 100
Driver Name: RTKVHD64.sys
Provider: Realtek Semiconductor Corp.
Driver Version: 6.00.0001.6343
Driver Date: 4/6/2011 15:33:48
Type: WDM
Other Drivers:
Acceleration Level: 1
Cap Flags: 0
Min/Max Sample Rate: 0, 0
DebugMessage: *********END dxdiag info.*********
Debug Message: CInitializationListener::OnSetContinentsPerPixelDataTail
Debug Message: CGalCiv3Shell::RequestInitializationState from: LoadingContinentTextures to: CreatingContinentData
Debug Message: Popup Manager Update: Unhiding TitleWnd