You really don't need software for this. That's a sledgehammer to crack a nut.
Most clubs use a simple peg system. The pegs are typically clothes pegs, and you can use anything from a wall-mounted board down to a scrap of cardboard.
There is an area on the board for each court, and when a group goes on court they put their pegs up there.
There is a waiting area (the queue). When players come off court, they put their pegs at the back of the queue (winners first). The player at the front of the queue chooses the next game.
Often there is a rule that you can only choose from the first 8 players (or 10, or whatever). This is designed to make sure people are not waiting too long while they get skipped over repeatedly. Peg boards can be devised that make this easier to see. At the most basic, you can cut out a piece of the board, or place a blob of blu-tack, to split the queue so that only 8 pegs will fit in the front part.
Often there are other rules. For example, a visitor is not allowed to pick; or you cannot pass over a woman twice; or you cannot pick a singles; or you have to do a lap dance for the chairman if you want to skip over him. This is England, after all.
In Scotland you might be able to leave out some of those esoterica.