I just included the new version of the wrapper into a project which used a former version of the wrapper and also experienced your problem ! It seems that Visual Studio doesn't include new files automatically, so you have to do the following :
-Go to the Solution explorer (on the far right) -Open the folder AcknexWrapper through clicking on the plus beside it -then click on the second symbol in the solution explorer "Show all files" -then right-click on the white/gray file called Flags in the solution explorer -and click on "Include In Project" -after this you can click on "Show all files" again !
