I noticed this isn't in the Compatibility List for this program, but the game indeed runs. It is just that the default configuration, for the game itself, has issues with Crossover. I submitted the application to the site, and since the instructions are to not describe how it works there, but to post it here in this forum right afterwards. The fix below is simple, but you need to do these steps in the right order.
Note: This assumes you used Codeweaver Crossover to install the latest version of Steam. (Best to use the default setup where it uses the Windows 7 bottle as Windows 10 brings about some display issues with the Steam launcher itself.)
After you install "It Lurks Below" within Steam, you want to launch the application. (if it is the first time launching, it'll install some extra libraries to complete installation, but not actually start the program)
Launch "It Lurks Below", one more time, to get it to go to the title screen.
It will appear to not get past the actual Title Screen, but actually it's not so much stuck as it isn't coming up with the right resolution to allow you access to the menu.
Use Command-Tab to get back to Steam and close "It Lurks Beneath". Steps 2 and 3 are necessary in order for the program to write the config file. It won't exist until you do these steps.
Open an explorer window, within your Steam bottle, and open the file at this location.
(You can also open up the explorer window by looking up the game's properties and "Browse Local Files" under the "Local Files" tab.
C:\users\crossover\Local Settings\Application Data\Graybeard Games\It Lurks Below\ilb_config.txt
The first three lines of the config file should show:
Change the 0, on lines 2 and 3, to a 1. The first three lines should now show:
Save the file and close the explorer window.
Launch the application again and it will work from then on. (At this point, my tests show the program running with no known glitches.)