How to make Bizagi Modeler actually nice to use
1) Fix your performance problems. Scrolling through diagrams is laggy, many operations even in simple diagrams make the program unresponsive for multiple seconds, opening different editor windows such as properties takes seconds, moving components and connections is unresponsive and laggy.
2) Be consistent. There are two different file/directory selection dialogues used throughout the program and of these the directory browsers is the wrong component to use in any situation. It does not have selection history and so you have to tediously open subdirectories every time from root when you want to use it. The traditional Open/Save dialogue is clean and easier/faster to use. If I have to test a process while tweaking it ever so slightly each time I don't want to select the same folder many many times within an hour by each time navigating to it with the directory browser.
3) Limit tedium and things that slow work process. When exporting to an image DO NOT open the image afterward, this is really bad for the workflow. When exporting an XPDL DO NOT put it in a separate sub directory from the location that I actually choose, this makes overwriting changes a chore since I have to open the directory in my filebrowser and move the file to its correct location.
4) This is the most important of them all. Listen to your users and don't give answers that clearly show your community personnel didn't read the message they are responding to but are giving stock answers instead.