Trouble Building WSJT-X on Slackware64-15.0

Has anyone succesfully built & run WSJT-X on Slackware64-15.0? I tried building WSJT-X 2.5.4, 2.6.1, & 2.7.0-rc2 on 15.0 and all fail to build and stop at the Italian translation:

Code:[ 45%] Building required Qt translations for language ca
[ 45%] Building required Qt translations for language da
[ 45%] Building required Qt translations for language en
[ 46%] Building required Qt translations for language es
[ 46%] Building required Qt translations for language it
QM-Format error
make[5]: *** [CMakeFiles/wsjtx.dir/build.make:241: qt_it.qm] Error 2
make[4]: *** [CMakeFiles/Makefile2:430: CMakeFiles/wsjtx.dir/all] Error 2
make[3]: *** [Makefile:156: all] Error 2
make[2]: *** [CMakeFiles/wsjtx-build.dir/build.make:73: wsjtx-prefix/src/wsjtx-stamp/wsjtx-build] Error 2
make[1]: *** [CMakeFiles/Makefile2:436: CMakeFiles/wsjtx-build.dir/all] Error 2
make: *** [Makefile:91: all] Error 2The above mentioned WSJT-X versions successfully build and run on Slackware64-current without any issues. Any tips or hints at what I can look at on 15.0 to build are appreciated!

Thank you.