The engine is just like Ren'Py, tab skip, right click save, it literally has everything Ren'Py does.
One annoyance I have is forcing the saves by chapter - you can't open the new and grab the old, but have to open in the old chapter, start the new chapter and save in the new chapter slots. I sometimes do this on other VNs, but not always, and it means you have to exit, go back to the old chapter and progress, save in new chapter for every path you're taking. This far in, my paths have gotten a little complex and numerous.
I've also had problems with the skip function - it seemed to want to skip unread text in at least one chapter and I didn't see a way to change that the way you can in RenPy.
So, while it has a lot in common, some of the nuances (some probably designed to make piracy more difficult) can be a PITA. There's also the screenshooting that is based solely on the 24 hour timeclock save - if you play anywhere near your local midnight and shoot items in a scene and cross midnight during the scene, your saves get out of order. If you're paying attention and rename before midnight, it becomes less annoying, but it's still an annoyance not simply numbering the shots the way RenPy does. The VN also doesn't "auto return" after the screenshot saves - you have to save manually save the shot, then click back into the game. While the RenPy screenshot save banner is annoying and takes too long to clear, this takes marginally longer and has an extra two steps.