reload interface while keeping data? I'm still learning the new 2.8 layout. I screwed up my interface somehow and I can't scroll in / out. 

I try doing load startup file, but it resets me back to the default cube.

How can I reset the interface while keeping the model I've been working on ?
You can save your project file and then (re-)open it without loading the stored UI. This can be accomplished through File > Open with the Load UI option unchecked.