I hope it isn't too taboo to resurrect old threads here but this isn't too old and has the perfect name...
My new Filco's enter key problem is different from OP in that the switch actuates just fine.
Mine just feels different/ less smooth from the rest of the board.
When I got the kb in the mail I had to re-seat the right shift and backspace keys because they were sticking up, I guess from some rough shipping.
After doing so though, they feel great.
My Enter key feels totally different from the rest of the board it's lighter, looser, mushier, and doesn't feel nearly as rock solid as the rest of this black Filco. It makes a plastic scraping noise and I can feel friction as well.
Other than that this keyboard is unbelievable smooth, especially the spacebar... soo good.
Pop it off and check the stabilizers? I'm just apprehensive and I don't have any lube(lol).