works as expected. Yay!
Setting one weapon with reload R and count C to be exclusive and also to use one shot at a time prevents other weapons from firing for the first R frames after is it fired. Furthermore, the weapon itself takes R frames after it hits something before it can be fired again.
If the shot doesn't hit anything, this means other weapons can fire for the interval (R, C+R). This is a method to make exclusive shots not actually be totally exclusive, so they stop all weapons for a short time, but they themselves take longer to reload.
Here is one implementation I've devise: Set up the exclusive gun so it never hits anything, and to submunition at the end of its life into an "actual" weapon. The net effect is a pause of R frames after you fire it during which none of your guns work. Then your other guns become active again. Then C frames later the submunition forms and the exclusive gun becomes active again.
I recommend numbers for the exclusive gun like R = 9, C = 19, so you can use it once a second, there's a one second delay between firing it and its submunition becoming active, and other weapons are only interrupted for a third of a second.
Depending on the graphic and behavior of the exclusive weapon, the one second delay could be a "charging up" or a "target acquisition" or a "countdown". In fact, if it's any of those things, you might want to be able to fire a second copy of it before the first finishes its countdown.
In that case, simply make the first submunition also not hit anything so it just continues the countdown for another two seconds or so before exploding or submunitioning into the actual weapon. That way you can fire one, wait a third of a second before you can fire other weapons, then another two thirds of a second before you can fire the first weapon again, then two more seconds before the initial shot goes live.