Etar Calendar not running in fresh build from sources

Trying to build Calendar app (to add my changes to obtain Opentasks integration) from main branch. After I build it I run and I get this error: Can’t convert to color: type=0x1

After investigating I have problems importing the e-ui.jar into the project: I found that it is raised because the strings as “@lineageos.platform” in color.xml are not being evaluated correctly. If I change the strings to regular colors I can run the app