How can i use the presentation slider? Is create_slider_overlay used for it or something else?
Firstly, get yourself an expanded version of header_operations.py, if you have not already done so (it is useful, as it provides insight into Warband commands); you may also check its WSE counterpart if you want to possess even more tools at your disposal. Secondly, acquire the latest version of Modding Guide to refer to when working with Warband engine. Thirdly, it is good practice to browse through the source code of many modules to see how things were scripted. You may want to skim through module_presentations.py of Native or another mod to learn stuff.
Personally, I recommend you reading