Ah, I think I'm having the same issue. Both me and a friend from Denmark have have attempted to play Dragon Commander but after last update it refuses to work.
As far as I know, the problem is that the joining player's game crashes as soon as the host starts the game. We have tested this several times on the campaign map. Whoever hosts the lobby can just play alone, and everything works there. However, the other player receives the "Dragon Commander has stopped working" message and then crashes to desktop.
For your convenience I have also added my system information from DxDiag.
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System Information
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Time of this report: 7/15/2013, 15:36:51
Machine name: -
Operating System: Windows 7 Ultimate 64-bit (6.1, Build 7600) (7600.win7_rtm.090713-1255)
Language: English (Regional Setting: English)
System Manufacturer: MSI
System Model: MS-7346
BIOS: Default System BIOS
Processor: Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz (4 CPUs), ~2.4GHz
Memory: 4096MB RAM
Available OS Memory: 4096MB RAM
Page File: 2790MB used, 5398MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
User DPI Setting: Using System DPI
System DPI Setting: 96 DPI (100 percent)
DWM DPI Scaling: Disabled
DxDiag Version: 6.01.7600.16385 64bit Unicode
