Thanks to some nice Tiertime developer we now have some header files with several definitions.
The new MacOS version (only available on MacOS-X App Store) does have several header files included. Folder: /Applications/UpStudio.localized/UpStudio.app/Contents/Resources/inc
2DModel.h
3DModel.h
3dmath.h
CFile.h
GElement.h
ListArray.h
PrintLink.h
Slicer.h
TTPrint.h
TT_define.h
WinTypedef.h
printparam.h
Very promising :-)