Looking at Aart Onkenhout's web page for coolmenu:
http://pbsite.milente.nl/coolmenu.html
The most recent release is 2.5 build 175, dated 10 July 2007. The Visual Studio 6.0 workspace and source code is available for download.
Partly for the challenge and partly for fun on a rainy weekend, I was able to import and upgrade the source into Visual Studio 2019 and with a few hours of work performing source code and directive tweaks (I'm really not a C++ person), I was able to get a clean compile and produce a new dll. I'd like to verify that it works, but I won't have the time to do that for a while. Eventually, I'd like to see what it would take to produce a 64-bit dll, now that I've got a clean 32-bit build.
I notice that Aart's is currently viewing this issue, so I'd like to ask if what I'm doing is OK with him. Aart, let me know it's OK or if you want me to stop and I will abide by your wishes.