In the link of my previous post, I mentioned that apps "Can't be opened" if the executable inside the *.app/Contents/MacOS/ folder does not have the execute bit set. You need to open the application "Terminal" (use Command + Spacebar to toggle Spotlight and search "Terminal") and copy paste this (click return / enter after you pasted)
printf "\nSelect the application that cannot open\n\n"; a="$(osascript -e 'POSIX path of (choose file default location (path to downloads folder) of type "APPL" with prompt "Select the application that cannot open")')"; if [[ $? -eq 0 ]]; then printf "(Re)Applying the execution permission to executable files..."; while read f; do if [[ "$(file -b "$f")" =~ "Mach-O 64-bit executable x86_64" ]]; then chmod +x "$f"; fi; done < <(find "$a"); if [[ $? -eq 0 ]]; then printf "done\n"; printf "\nRemoving extended attribute com.apple.quarantine from app..."; if [[ "$(xattr "$a")" =~ "com.apple.quarantine" ]]; then xattr -r -d com.apple.quarantine "$a"; printf "done\n"; else printf "already removed\n"; fi; printf "\nPlease wait until application launches..."; open "$a"; printf "done\n"; fi; fi; printf "\n"
Oh right, I forgot this isn't going to open right unless you replaced the internal jre folder beforehand