having a problem with campaigns with over 20 missions; now and then when i finish the 21, 31, 41,... mission in a campaign, cfs closes to windows instead of starting the debriefing. When i restart cfs and reopen the campaign the last mission ain't showing and i have to refly it to continue the campaign, to encounter the same problem and get in  a loop of reflying the same mission.
The only solution i found is to open the pilotlog and manualy change it as if the mission was flown.
So i know a solution but have no idea what is causing this, but noticed that for the pilotlog the 21the mission is were the missioncount changes from 10's to 20's so it looks as if the pilotlog does not know that 20 comes after 19, 30 comes after 29,.... ???
Does anyone know a solution or is this a windows XP related problem?

BTW: i am working on spitfire, hurricane and BF109 BoB campaigns with each 50-60 missions (containing new missions and reworked ones) based upon the real events, so i hope that someone can solve this problem with more than 20 missions in a row or i should split up my campaigns

the missions work perfect in single mission play, and give the debriefing after ending and when replaced by another from whom i am sure it should work, the problem apears in that mission.
The cmg file is formed the way you have mentioned.
The problem occurs only when in the pilotlog [mission.0.20] should be formed (also by 30-40-...).
I am still in testing phase for the campaigns so they are not uploaded yet. If i can not fix the problem before the work on them is finished i will send them to you if you want them to test , just do n't expect them to soon: i am testing them while my little girl (born on 15 sep) sleeps on my left arm.

The only thing I can add to Hagar's comments is that the original campaign mission count in CFS1 is 18.
Although Windows sorts file names according to the 1st digit, with "0" preceding "1" (not only a file name starting "10" would be stuck between "1" and "2" but so would "101, 12..."), this should not affect your campaign cmg file (but, as Hagar indicates, over 19 missions may not have been accounted for in the original programming). If test forming your own campaign in the mission folder, however, this will make a difference, so temporarily name the missions accordingly (in lieu of alphabetical listing) if you want them to appear in order.
A suggestion, though no true fix, is to split your campaign into 2 (or more) parts. I have not tried refering one cmg file to continue to the next but it's thought we might try; elsewise you can choose either as individual campaigns rather than consecutively.