@Gaston: Looks like you're missing some message files according to the error.log file, check these files and install them into the DGEN folder:
http://www.mission4today.com/index.php?name=Downloads&file=details&id=2615
these files often solved problems in the past
@Gunny, pleae try also these files posted above, i assume you may have the same problem,
if not, it can also be a problem with the british ranks and medals, try this:
http://www.mission4today.com/index.php?name=Downloads&file=details&id=629
should solve your problem
I had this "Beep" and installing the download from link 1 fixed it, however upon choosing a Spitfire F1 1939* campaign my pc froze.
I exited with CTRL+ALT+DEL and tried again, this time with a Hurricane (default choice in the fake war) this worked instantly.
I exited that and tried the Spitfire F1 1939* again, this time it said "this campaign already exists" It doesn't however

As my career screen was blank, there were no existing campaigns.
I chose overwrite, yet again the PC froze, it seems to be a problem with the Spitfire F1 1939*.
Would you know what the issue could be?
Incase it makes any difference, my Ranks and Medal names are in Russian in the RAF campaigns (they are English everywhere else.)
Edit, bit late so I will have to be more precise tomorow, but it seems to crash D-gen each time I try a mod spitfire campaign, late versions that I think are Madox models, let me have a Spitfire campaign, the others from 1939-1940 crash the game for me.
Just noticed this, it is the only Error file I have for Dgen.
= DGen 4.0.8.6 (17/04/08) =
seed: 54528402
DGen initialization. Side: gb, Rank: 0
MaxBomberSkill=3
Distance=Any
Length=VeryLong
AI=Normal
Missions=Normal
AirIntensity=Medium
GroundIntensity=Medium
SlowFire=5.0
PromotionRate=1.000000
Career ID: Gb5
Normandy:France40
Inherits France40
ReadDB sorties:1
PlayerWing found:RAF_No003SQN
TestWing(f,s): RAF_No001SQN 0 00
TestWing(f,s): RAF_No003SQN 0 00
TestWing(f,s): RAF_No081SQN 0 00
TestWing(f,s): RAF_No087SQN 0 00
TestWing(f,s): NN 0 00
TestWing(f,s): NN 0 00
TestWing(f,s): NN 0 00
TestWing(f,s): NN 0 00
TestWing(f,s): NN 0 00
TestWing(f,s): I_JG26 0 00
TestWing(f,s): I_JG2 0 00
TestWing(f,s): II_JG2 0 00
TestWing(f,s): III_JG2 0 00
TestWing(f,s): I_JG26 0 00
TestWing(f,s): I_JG2 0 00
TestWing(f,s): II_JG2 0 00
TestWing(f,s): III_JG2 0 00
Blue skill set: 5 30 30
Red skill set: 8 40 40
TestWing(f,s): III_JG2 0 00
TestWing(f,s): III_JG2 0 00
TestWing(f,s): I_JG26 0 00
TestWing(f,s): I_JG27 0 00
TestWing(f,s): I_JG2 0 00
TestWing(f,s): I_JG2 0 00
TestWing(f,s): I_JG26 0 00
TestWing(f,s): I_JG5_3 0 00
TestWing(f,s): I_JG2 0 00
TestWing(f,s): I_JG26 0 00
TestWing(f,s): RAF_No081SQN 0 00
TestWing(f,s): RAF_No081SQN 0 00
TestWing(f,s): RAF_No087SQN 0 00
TestWing(f,s): RAF_No091SQN 0 00
TestWing(f,s): RAF_No003SQN 0 00
TestWing(f,s): RAF_No091SQN 0 00
TestWing(f,s): RAF_No091SQN 0 00
TestWing(f,s): RAF_No091SQN 0 00
TestWing(f,s): RAF_No091SQN 0 00
TestWing(f,s): NN 0 00
TestWing(f,s): NN 0 00
TestWing(f,s): NN 0 00
TestWing(f,s): NN 0 00
TestWing(f,s): NN 0 00
Inherits operations from DGen\ops_WFFrance1940.dat
Groups Y, U or Z not specified - line ignored
Dangerous areas
Red:2 Blue:4
Can't open Message file DGen\GB_MessageRu.dat