Completed 3 missions in arcade mode ，but no achievement. Completed other missions in mission mode，got . But try the 3 in mission mode ，nothing .
So you can't complete 6 chapter achievements ，and try them in mission mode again neither.

If you never mind lose your progress：

delete the folder ：C:\Users\****\AppData\Local\mslugx
Folder “mslugx” is where game data save.
But I didn't just delete “achievements” or just delete “missionunlock”，may you can have a try.

Which achievement you have gotten will not lose.

街机模式下无法解锁6个游戏进程的成就，可以通过删除以下路径的文件夹达到。
C:\Users\****\AppData\Local\mslugx
该文件夹便是保存的游戏进程及设置数据的地方。
删除后再在任务模式进行，没有解锁的进程成就在完成后就可以解锁。
不过我没试过只删除文件夹中“achievements” 或 “missionunlock”这两个文件，也许你可以试试。
已经解锁的成就不会受影响。