I tried to test and after 17th selection of map, the game crashed :O
EDIT: If cannot put 21 maps, can I put one bonus level then AFTER final level? I mean when you beat the whole campaign, an extra level occurs after that, is it possible?
EDIT2: INTERESTINGLY! I can actually PUT 21 maps! It works, the vireframe itself have corrupted insomewhere other campaign where I did copy or so
EDIT3: This is interesting, it actually takes off one map from the campaign. Try it yourself, try to make a campaign, which has 21 levels. Do you get same problem? after 16-17th map it goes black, but still I can skip it and go further. Problem with me or?
EDIT:4 Yeah, I can actually put 21 maps, but 17th one is taken on black screen, but I can still skip it by CTRL+F10 and then comes 18, 19, 20 and 21
EDIT5: Warning: Block [map03681] not found in Campaign config file. <- It is there, but it says this? :O EDIT6: This was typo as 003681, my bad
EDIT6: All typos fixed. You can have more than 20 levels! Not sure if still counting 5 extra levels, so I keep 4 only ( and decent ones )
But I can confirm. You can have more than 20 levels on campaign!