First, I want to give you a longer review and a bunch of improvement suggestions in the future but for now I need to submit a couple of issue that I've found.

1. Grabbing the Mouse: The documentation says that you need to just press F11 to capture the mouse, but the application requires you to press Ctrl+F11 to grab it.
2. Sound Issues: There is a game called AMOK which is a 3D mech game. When running this game using this application there is no sound even after verifying that it was turned on. The sound does work in normal DOSBox, DOSBox-X and DOSBox Staging though.

Thank you for the feedback.

Regarding 1. the documentation says:

A few system functions are bound to various F-keys, accessible while holding the hotkey modifier which by default is the Control key. The hotkey modifier can be changed in the System Settings. These are the hotkeys: …

So it does mention that by default you hold the Control key and then use the F-keys. You can change Ctrl to be something else. This is important if you want to run a game that uses Ctrl+Fx for its own functionality.

Regarding 2. try running SETUP maybe? If it works in DOSBox it should work here.