Sounds like you havent disabled the DPS 2 keymap under FTL DPS Keys.. That means the keymap DPS 2 sends a "2" key and at the same keypress your sending "2" from your twostep keymap. This will result with something like 222,222,222,222, etc when spamming.
I made a toggle keymap. What this one did was disable the DPS 3 keymap and enable the twostep keymap (both those keymaps with button 2 as hotkey). That toggle keymap bound to a key you normally dont use (for me it is insert key).
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