Hi Krzysztof, you do not need to use the numbers on your own applications and scripts. The ideas of using number series are several. The first one is that folders and files together an index so that documentation and tagging becomes easy. Example 1.HR\1.Application\3.HR-app\1.qvdloader.qvw could also be referenced as 126.96.36.199 in publisher tasks and documentation. The number series is also seen as a differentiator between custom code and built in QDFcode in the sub function library. There is also a new sub function in development that will identify global variables on the number serie and use the name after "dott" as the variable name.
A tips: In the latest release there is a sub function named 99.loadall.qvs if you add a include statement to this file in Shared folders Custom.qvs, all the built functions will be loaded into all applications by default and you do not need the includes in the applications any longer. hope this helps?