So when you release these new versions every other day, does that mean I have to uninstall the previous version and download new one?
Of course you should download and install new one!
About to uninstall or not to uninstall:
Combats are designed to be compatible to be overwritten on update between big versions.
If you install combat 4.3.2 (version of release 4.3) english version into C:\war2Combat43en and install combat 4.4.0 (version of 4.4) into C:\war2Combat44en (as i do), and then you will install combat 4.4.2, it will ask you to overwrite previous release of 4.4 release: to install C:\war2Combat44en, and that is recommended way.
Combat remembers installation folder between version of 1 release and asks you to install next 4.4.x to the previous 4.4 installation folder.
But you can also install combat 4.4.2 to common C:\war2combat folder with previous version 4.3.x or earlier. Everything should work properly even if didn't uninstall it before.
Common concept for all combats since 3.01:
You feel free to install any version of combat to a folder with previously installed combat of another version, everything will work fine, they will use saves and maps from previous installation in this folder.
At the same time, you feel free to install every combat version to different folder, then they will not interfere between folders.
Of course, installing combat into folder with GoG is not recommended (combat will work anyway though).