Svrl

Dear developer and community, I would like to ask for little help to my questions below: Is there any proper documentation or guide available for this application? I would like to ask also for more information about environment, as which version of PhP or what next is also important to assume please? * Is your application free to use? According to the used jpgraph license it is not for commercial use, am I wrong? Application is also throwing same error, either on php 5.6 or 7.3: Fatal error: Call...