MacOS Catalina: when I try to open the application, it says "The application 'Cascadio' cannot be opened."

I went into Terminal, went to folder Cascadio was in, then typed: cd Cascadio.app/Contents/MacOS

then: chmod +x Cascadio

And then right-clicking the file, selecting Open then Open again to get past the error message that the developer can't be identified.

Thanks for letting me know about this.  I have an older mac and can't upgrade to Catalina currently to try it out.  I'll try to get this straightened out and provide instructions or a new build.

I get the same error in Mojave if I unzip it using the native Archive Utility, but not if I use a third-party program like Keka.