Configuring qcomicbook in Slack64 current was incomplete, errors occurred when SlackBuild is used

Hi, I am running Slack64-current. I tried to install qcomicbook with the command #./qcomicbook.SlackBuild but configuring was incomplete as errors occurred:

Quote:

-- Detecting CXX compile features - done CMake Error at /usr/share/cmake-3.21/Modules/FindQt4.cmake:1314 (message): Found unsuitable Qt version "" from NOTFOUND, this code requires Qt 4.x Call Stack (most recent call first): CMakeLists.txt:17 (FIND_PACKAGE) -- Configuring incomplete, errors occurred! See also "/tmp/SBo/qcomicbook-0.9.0/CMakeFiles/CMakeOutput.log". bash-5.1#

Besides that, from that moment on I could not download the .cbr and .cbz files anymore. I can download .pdf and .doc files but not the ones I mentioned.