I can not compile because I get the following error
In file included from UTFT_Buttons_Bitmap_Demo.ino:31:
C:\Program Files (x86)\Arduino\libraries\UTFT_Buttons/UTFT_Buttons.h:35: error: #error : You will need UTFT v2.41 or higher to use this add-on library...
It seems that in the include file "UTFT_Buttons.h" there is a check for the version of the library at line 35.
The library is telling you that your version of UTFT is too old.
If you do have the new version, perhaps it can't find (a part of) the library. Perhaps the library is not properly installed.