I stole this idea from other software... If you want to move a bet, you right-mouse click the price you want, and the bet will move there. If there is more than one unmatched bet, the closest bet will be moved.
In the example above:
If I want to move my BACK bet to 4.8, I would right-click 4.8 on the ladder
If I want to move my LAY bet to 4.6, I would right-click 4.6 on the ladder
If I right-click at 4.7, nothing will happen - both unmatched bets are the same distance away
BotBeetle already has Stake mode and Liability mode. My suggestion is to add Payout mode (Total Stake/Odds), so if my total stake is £10, and I place a back bet at odds of 4.0, the software would place a bet of £2.50. I know I can do this already with the dutching module, but I prefer to use the ladder or grid, as it is easier to read the market and quickly select the odds I want.