The option is not obsolete. The IDE just reads this one option from the file. But it can still be used on its own. And if specified, it overrides the setting in the file.
So you can also run one and the same install, with different config.
The windowstyle I do not know. Better post a new thread, with a subject related 2 that question. Or just open the lfm files and look yourself. (Yes you have to search them, so would I have to do)