I totally agree the "new project" dialog is dodgy and confuses people.
I think we can do better - instead of entering the project name and
guessing base path based on that, we can go the other way round; first, get the base path and then, from the base path provided by the user, set the project name and project file.
This approach seems better than the existing confusion.
a. First pops up a open directory dialog to specify base path
b. After that, opens the (currently used) New Project dialog which is pre-filled in the following way:
Name: The last directory in base_path
Filename: depending on "store project file inside the project base directory" settings either in base_path/(1).geany or projects_dir/(1).geany Base path: path specified in (a)
Can I suggest instead of serial popups, have a single popup with base path at the top with focus on it and the other entries insensitive. When the base path is entered fill them as described and set sensitive for users to twiddle as needed.
Use "Store project file inside the project base directory" by default
Personally I usually do this anyway, what do other people think?