Plot hole: In the second Shrek movie, we find out that Fairy Godmother and the King had a deal that Prince Charming would save Princess Fiona from the keep, hence becoming her true love and breaking the curse. In the fourth movie, we start with Rumple monologuing about how he almost had the Kingdom by signing a deal with the King. Why would the King be so desperate to try and reverse the curse by signing a deal when he knows he has a prior attempt through Prince Charming, assuming it would take the same time for the messenger to return with news about Charming and Fiona either way?
Plot hole: Rumpelstiltskin is at a low point in his life, so he's in the back alley eating from the garbage cans. He gets the idea to trick Shrek so he can take over Far Far Away, and bribes him with a rat cooking in the oven and eyeball martinis. Why is Rumpelstiltskin eating out of the garbage when he has a plump rat with vegetables roasting and eyeball martinis? Even if just the vegetables appealed that's better than garbage.